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Richard230
27 February 2013, 1602
I just picked up the March issue of City Bike, a free San Francisco monthly newspaper-style magazine. The new 2013 Empulse R is reviewed in a full single-page article on page 19. Unfortunately, it didn't make the front cover (like my Zero did last April). (The cover story is labeled “Splitting Headache”, about motorcyclists splitting lanes in California.) Here are some riding impression excerpts from the article:

One review was written by Gabe Ets-Hokin, the magazine's editor-in-Chief, (titled “Lost in Transmission”) and the other review was written by Alan Lapp, Art Director, (titled “Assault with a battery”).

Gabe praises the Empulse for its top speed, mid-range power, good handling and decent range. However, he says that it still does not have enough range for sporting weekend rides and you may be disappointed. “Until range gets longer and charging stations become ubiquitous, electric vehicles are best for trips of defined range.” (Nothing new there.)

Things get a little ugly when he starts talking about the gearbox: “Which brings me to the gearbox. I don't get it. It's adds little to the experience, if you ask me. Neutral is in between second and third for some reason, but you don't really need neutral – the bike rolls freely in gear with the clutch engaged. Comes to think of it, you don't really need the clutch, either, although it does make getting under way smoother, a role throttle-management software handles on other e-bikes. I found myself shifting out of habit, but it felt like I was playing a video game with a disconnected joystick. I'm sure if I was doing a trackday – or just spent a lot more time on the bike – I would start to figure out how to best use it, but my quick impression is Brammo should bin the clutch, make the transmission a two-speed (city and highway), and carve 40 pounds off the bike – or use the extra space and weight for more battery capacity.”

“So I am surprised I'm saying this, as I've been champing at the bit to ride this thing for years, but I found it to be too much like a conventional motorcycle. It''s 470 pounds, and though you don't really feel the weight most of the time – the CG is comically low, like a scooter's – you know it's there, which diminished the playful character of the electric motor.”

Gabe finishes his review with: “And it's really fun to ride, giving up little to any middleweight commuter I've ridden. Would it be a rational purchase? Not really. But what motorcycle really is?”

Alan Lapp says: “It was disappointing how the motor controller – the computerized rain that examines rider input, and manages bike output – steps in and nannies all the fun out of having a clutch to play with. Should a rider try to do a wheelie (the motor is definitely powerful enough) by revving the motor and dumping the clutch, all that results is a lurch as the controller compensates to eradicate this hooliganism.

Regarding the transmission, more oddness ensues: neutral is between 2nd and 3rd. The rations are very closely spaced, and launching the Empulse R in 1st gear results in satisfying acceleration. However, launching in 3rd or 4th gear does not blunt the acceleration very noticeably. I suspect that most riders will tire of the notchy, clunky shifting and leave it in 3rd around town, only shifting to 6th on the freeway.”

Mr. Lap goes on to praise the Empulse's performance, ride, stability, handling and brakes and he says the “design is handsome”. He finishes his review with: “It seems to me that e-bikes are maturing rapidly, but are suffering some growing pains.”

jazclrint
27 February 2013, 1751
Arrgh. The reason for 6 speeds was because 2 or 3 won't work. That's the first time I have heard anyone say that the transmission detracted from the ride, or at least didn't add to it. That is interesting. The low center of balance comment is new, and I question it.

mechanic
27 February 2013, 1930
Arrgh. The reason for 6 speeds was because 2 or 3 won't work.

100% unsubstantiated BS... Ridicules statement!

Nuts & Volts
27 February 2013, 2117
100% unsubstantiated BS... Ridicules statement!

Not BS, it is very difficult to shift over too large of a range from one ratio to ratio. It can cause excess wear or extreme impact loading on the gear teeth. This can cause limited lifetime and higher risk of tooth failure. It's also harder to rev match without locking/skidding the rear wheel. This works against the need to have gear ratios far apart in order to gain the real advantages in acceleration and top speed that can be possible with a transmission.

Somewhere Brammo has hinted at or stated that this is one of many reason they have 6 gears. I'll post if I find the thread/post

mechanic
27 February 2013, 2209
Not BS, it is very difficult to shift over too large of a range from one ratio to ratio. It can cause excess wear or extreme impact loading on the gear teeth. This can cause limited lifetime and higher risk of tooth failure. It's also harder to rev match without locking/skidding the rear wheel. This works against the need to have gear ratios far apart in order to gain the real advantages in acceleration and top speed that can be possible with a transmission.

Somewhere Brammo has hinted at or stated that this is one of many reason they have 6 gears. I'll post if I find the thread/post

Really... Even more BS!

Ratios are only relevant to torque curve.

I don't have the energy to debate all your points- on your level.

Anyway sounds like you already have a source for all your electric transmission insight. LOL

FYI Honda MotoGP actually has two ratios selected at any one time and in F1 the engine rpm is raised accordingly to matched each computer (corner by corner) downshift (without a clutch) in mili-seconds. Big world out there, creative and better solutions unless you just keep regurgitating the same BS party line- good luck.

Nuts & Volts
27 February 2013, 2213
Really... Even more BS!

Ratios are only relevant to torque curve.

I don't have the energy to debate all your points- on your level.

Anyway sounds like you already have a source for all your electric transmission insight. LOL

FYI Honda MotoGP actually has two ratios selected at any one time and in F1 the engine rpm is raised accordingly to matched each computer (corner by corner) downshift (without a clutch) in mili-seconds. Big world out there, creative and better solutions unless you just keep regurgitating the same BS party line- good luck.

And there goes the productivity of another thread...I like the view from my level a lot better thanks

teddillard
28 February 2013, 0245
Arrgh. The reason for 6 speeds was because 2 or 3 won't work.

wuuuut? Care to elaborate? (...on any level lol) I guess Kyle is on it but...

Pretty much what I've decided is that 2 or 3 would be perfect if you must run a transmission... and that the reason Brammo's running a 6 speed is because that's what they could buy.

jonescg
28 February 2013, 0715
Surely they could have a non-synchromesh gearbox with two speeds (city, top speed 70 km/h and highway, top speed 160 km/h) which you get off the bike and pull a lever to engage. Again, only if you really need a gearbox.

Richard230
28 February 2013, 0900
I seem to recall that BrammoBrian also stated that one of the reasons the Empulse was using a 6-speed gearbox was to reduce the drive train speed differential between gears. That could be, but I would think that their electric motor has a lot less inertia change to accommodate when shifting than does an IC motor, with all of its heavy spinning parts, many of which are going around and around and up and down. In fact several reviews of the Empulse have mentioned that the motor spins up so fast that it is almost useless to try to use the clutch when taking off from a stop, as it is just about impossible to hold the motor at a steady rpm when it is unloaded so that you can slip the clutch for a smooth takeoff. As previously mentioned, modern speed-shifters seem to be able to accommodate engine speed differentials when shifting between gears rather well, even when the shifting only takes a fraction of a second. Right now I am in the two-speed camp, based upon my experience with my direct-drive Zero. A low gear would be great when taking off from a stop up a steep hill, but once you get moving, a single speed seems to work very well in my experience. Plus, it would seem that most racing elmoto designers would agree with me. Once you get up to speed, a gearbox is just something that takes up space and weight and is one more thing that could break.

I still suspect that the real reason the Empulse has a six-speed box is because that is what was available from the gear assembly manufacturer that was off-the-shelf and would accommodate the torque produced by the motor. While there certainly are many three and four speed transmissions in the world, most of those are installed in relatively low-powered scooters and Asian transportation vehicles and would not be suitable for the Empulse's torque. I also believe that marketing a 6-speed motorcycle is easier if your market of interest is current IC motorcycle owners and performance motorcycle magazine editors (most of whom are ex-racers), whom are used to a 6-speed gearbox.

One thing that I am still mystified about is why neutral was placed between second and third gears? Since neutral seems to be mostly useless in practice, I wonder why it was located there? Could it have something to do with the design of the available gear-set?

Another thing that was brought up by Alan Lapp last year when I was having a discussion with Gabe and him about the possible design of the Empulse's transmission was that it could have used a "slipper" or centrifugal clutch (sort of like what was used on the old Honda step-throughs, to accommodate the drive-train inertial stresses when shifting between gears. Apparently Mr. Lapp is a big R/C car enthusiast and he told me that "slipper" clutches were used in that sport and they could be set using spring tension devices to allow slippage when shifting between gears. Many years ago I used to ride my brother's Honda 90 step-through and its three-speed centrifugal clutch seemed to work OK when shifting between gears without touching the clutch lever.

Finally, I would like to mention that plenty of large motorcycles in the past used two and three speed gearboxes (although most had a hand shift and a foot operated clutch), including the mid-1970's Honda 750 automatic and the 850cc Moto Guzzi Convert of the same era and they seemed to work OK - even if they weren't a marketing success.

Having said all that, I am happy that Brammo chose to install their relatively complicated 6-speed transmission. Without their product how would we ever be able to continue our transmission discussions and continue to debate this issue? How many among us can afford to design and build a working elmoto with a 6-speed transmission? I say, let them do it and we can watch to see how it all works out. :D

Attached is a photo of me on my brother's three-speed Honda 90. Sorry about the white denim suit and funky helmet. :O At least the gloves look OK.

ZoomSmith
28 February 2013, 0935
Without their product how would we ever be able to continue our transmission discussions and continue to debate this issue?

LOL

Shineysideup
28 February 2013, 2119
100% unsubstantiated BS... Ridicules statement!

Wow how many armchair engineers here that have never ridden the Empulse? Yes, if you actually test ride one for more than 5 minutes, you will surely experience the utility of the transmission and the appropriateness of a 6-speed one to keep the motor in either the sweet spot for economy (5000 rpm) or for power (6000 or 7000 rpm for Sport mode and Normal mode).

Or you could remain at your computers and sling BS at a sweet motorcycle design. Whatever floats your boat.

Shineysideup
28 February 2013, 2126
The low center of balance comment is new, and I question it.

I too found that comment really irrational. Actually the COG is almost precisely in the center of of the bike and this bike handles like it's glued on rails. Best handling bike I've ever ridden. Many other reviewers have raved about how confidence-inspiring this machine is in the twisties.

Shineysideup
28 February 2013, 2130
Pretty much what I've decided is that 2 or 3 would be perfect...

And you've decided this conclusion based on what exactly? Riding the Empulse in a wide variety of settings and terrain for over 1800 miles? Or some other criterion?

moon
28 February 2013, 2242
Whoa there hoss, we're all friends here, no need to be uncivil. :confused:

teddillard
01 March 2013, 0156
And you've decided this conclusion based on what exactly? Riding the Empulse in a wide variety of settings and terrain for over 1800 miles? Or some other criterion?

Endless tedious discussion, and lots and lots of data posted here by contributing members, actually, since nobody up until the Empulse in the last few months actually had an electric bike with a transmission of any sort except Brutus.

So since I DO actually build bikes here and there, yes, I had to make a decision about what all I thought would work best. Sorry if that offends you and "your" brand.

Welcome to ElMoto v4.0. Enter the Fanboys. :mad:

Skeezmour
01 March 2013, 0957
As we at Brutus have even moved on from the transmission for our use. It worked great when we had somewhat limited power output and also allowed us to quickly test multiple gear ratios. Then again we are not targeting 150mph+. With over 100kw and a gearing for a top speed of 115mph we have enough power to make our 600#+ motorcycles smoke the rear tire.

mechanic
01 March 2013, 0959
Wow how many armchair engineers here that have never ridden the Empulse? Yes, if you actually test ride one for more than 5 minutes, you will surely experience the utility of the transmission and the appropriateness of a 6-speed one to keep the motor in either the sweet spot for economy (5000 rpm) or for power (6000 or 7000 rpm for Sport mode and Normal mode).

Or you could remain at your computers and sling BS at a sweet motorcycle design. Whatever floats your boat.

This thread was started by a two journalist that rode the Empulse R 6-speed transmission and did not like it! This is far from arm chair engineering this was an actually review.

I left a very relevant "engineering hint" in my last post which went completely unnoticed so I will make it a more obvious.

There are two mechanical tools that can manipulate engine/motor characteristics; overall final drive ratio and transmission ratios.



Overall Final Drive Ratio:

It is rear wheel torque that driver/riders respond to. Most vehicles multiply their engine/motor torque with final drive ratios to increase rear wheel torque/acceleration/performance. (Done poorly like many e-motos and the result is a large rear wheel sprocket, more unsprung mass and more drive inertia and resistance)

Most modern sportbikes have an approx. 2.5:1 primary drive (crank to clutch/gearbox) X an approx. 3:1 final drive = approx. 8:1 final drive.



Transmissions Ratios:

Want to move a vehicle? then you want to use the engine/motors "best" torque. If your engine/motor has a torque curve like the peaky 125cc 2-stroke; peak torque at 11,500, starts to dramatically falling after 12,500 and produces little before 10,500 then you need a transmission that allows you to work within the 2,000 "power-band" range.

Fastest method to acceleration a 125- pull in the clutch rev to 12,000 and slip the clutch keeping the motor at it's peak torque/acceleration. Once the motor hits 12,500 upshift and the motor (designed by the best motorcycle engineers in the world) will magically drop the motor to 10,750 right in the beginning of the power-band, accelerate through that and upshift again and again and again.

The transmission is designed to reflect and match the torque curve of the engine/motor. If the ratios are too wide then each shift results in lowering the engine/motor revs below its power-band and a stall in acceleration results. Design the ratios to narrow and each shift results in, well... very little, disconnected and kind of pointless (sound familiar)

If nothing else, by now it should be understood/accepted (by real or armchair engineers) that electric motors have a very different torque ratio than 125cc's (or any ICE engine's) and if you know nothing else, you should also be able to imagine that the transmissions/ratios will also need to be different.

FYI- Back in the day 50cc Grand prix bikes had 8 speed transmissions and LSR had 12 speeds (they made NO torque)

Most electric motors have a very wide power-band, peak torque is often 1/2 of the motors total RPM. If an electric motors torque curve is more linear and is sustained over a larger rpm range than it should be perfectly clear that the gear ratios would also need to be further apart. Wider gear ratios means less gears (every motor is power limited on the max ratio it can carry)

As far as the other BS it is still BS: electric motors have too much torque and wide ratios break teeth? BS, Teeth are not even part of the gear shifting mechanism this is accomplished by forks and dogs and ICE load transmissions and teeth 10'sX greater than any electric motor due to outrages peak power pulses during combustion. As far as down-shifitng, sliding? BS, only an electric motor can have almost no engine breaking, the only limitation is the motors max RPM and slipper clutches have been widely used for over a decade now. As for peak efficiency? Then design an automatic transmission because riders cannot shift to efficiency as it is transparent to the rider.

I think you need to look no further than the electric race bike for your answer, if anyone could go faster and farther with a transmission then they would and when a transmission does show up- it won't be a traditional clutch/6-speed clunky solution.

Back to my (electric) armchair.

PS- Trying to justify excessive transmission slop and clunks and locating neutral (which is not even needed) between 2nd and 3rd- enough said.

teddillard
01 March 2013, 1029
Awesome post. Thanks.

Natas Damien
01 March 2013, 1306
http://youtu.be/9BMEr-BvaAo
Tacita T-Race enduro/rally electric motorcycle with multiple speed gearbox at Merzouga Rally 2012
~100kms of track travel in rally race conditions
http://www.tacita.it/en/
http://www.facebook.com/tacita.trace

flar
01 March 2013, 1538
Excellent analysis of why the reasons to use a transmission for an ICE motorcycle don't apply to an electric motorcycle.

But... There are a couple of other issues that aren't really addressed in that analysis.

First, disclosure - I purchased an Empulse R recently and chose that motorcycle over a 2013 Zero based on back to back test rides. I am also a skeptic as to whether an electric motorcycle should have a transmission and the transmission on the Empulse was not a selling point to me (I got it more for the handling and the more immediately useful L2 charging compared to the present-day usefulness of the charging options on the Zeros, with a nod towards the more exciting styling which I could easily have lived without if I enjoyed the riding experience of the Zero better than the Empulse - and I did not).

With respect to the article - I have yet to track down a hard copy, so all I have is Richard's quotes to go on, but I've heard that it was overall positive but that they had issues with the transmission. I'll note that just about every quote in Richard's OP mentioning a problem with the transmission is contrary to the specific instructions I was given on multiple occasions on how to use the transmission. How it affects launching is irrelevant because the specific instructions in the manual recommend in all capital letters to "NOT" use the clutch on launching. Expectations of a huge motor inertia to make dumping the clutch have any effect are somewhat ignorant of the size and mass of an electric motor (particularly the relatively small motor on the Empulse) and contrary to the recommendations I was given. Expectations that you would need to use 3rd gear as a single "city gear" are contrary to the recommended RPM ranges which indicate that any "city speed" (indeed any speed below highway speed) can be had with 1st gear and in fact are in the recommended best effect band for 1st gear. In short, I wish someone had given them the approximately 1 minute briefing on how to use the clutch and transmission on the Empulse as it would have radically changed their impression of how to get the most fun out of the bike and they would have spent far less time on procedures that are both non-optimal, but actually recommended against. Sigh.

Speaking as a transmission skeptic, I still look forward to a direct drive street motorcycle that provides everything that the Empulse provides (the 2013 Zero was pretty much just about there with their new motor, but they were a fair bit behind on chassis and suspension - I suppose I could have bought one and then upgraded suspension components as an alternative, but the Empulse met all of my needs just fine in stock form). Until then I am in no way unhappy with the transmission on the Empulse and, in fact, am finding it kind of fun in a nerdy way. It may not be a huge gain, but if I keep it near its efficiency peak then I do get a small boost in range. With respect to the drivetrain clunk - 2 tips can pretty much eliminate it and I completely internalized those techniques by the time I was out of break-in (600 miles).

With respect to the transmission analysis, I have a couple of additional thoughts to consider.

A transmission not only allows you to keep the engine/motor in a particular RPM range, but it also changes the mechanical advantage that the motor has on the drivetrain/rear wheel. The RPM range issue is key for ICE, but the mechanical advantage is important for any vehicle. If you want a single gear 100MPH motorcycle that also does a very fast 0-60, then the top speed target fixes or at least places a lower limit on your gearing choice and you then have to beef up the motor to meet your low end acceleration needs. If you provide gears then you can get that 100MPH top speed with one gear and also have excellent off the line acceleration with another gear. I agree that we should be able to engineer our way into powerful enough electric motorcycle motors the way Tesla has done for cars, and Brammo has even done that with their race bikes, but the costs they were incurring to get this much performance out of a direct drive motorcycle were out of line with what they wanted to bring to the street. They claim that using a smaller and more modest motor with a transmission came in much cheaper than the more powerful motor mated to more expensive higher voltage power systems. I can't support or refute those claims, but it is important to note that they didn't use the transmission to "keep the motor in its power band" - they did it to provide both high top speed and fast launches on a motor and controller that were cheap enough to keep the price in the teens. An analysis of whether they are kidding themselves would have to target those properties and not stray off into a straw man argument about ICE power bands.

With respect to 3 gears or 6 gears... I too heard that the primary reason was to use a stock gear set. It may have been just one of many reasons, though, and the particular employee who was quoted was simply more invested in that particular reason. I'll note that one issue with an electric motorcycle with a clutch lever and transmission is that it is very easy to redline the motor while shifting if you aren't very careful with the throttle during the shift. That is because the motor has so little resistance to spinning up (and one of the reasons one should never expect to "dump the clutch" with it and have anything meaningful happen). As a result of that, many (most?) of us use clutchless shifts which make it essentially impossible to redline the motor. Aren't clutchless shifts easier to perform with narrow gear ratios? Also, once you have gears, it's probably not that much harder to provide 6 - especially if it means using fairly standard parts - and it provides a wide range of fine tuning. It may not be "critical" to be in a particular RPM range, but it does have an impact and so if you want to pay attention to it and optimize efficiency then having lots of choices gives you more control. I'm not talking about constant gear hunting while in the mountains, but more when you get up to speed for a longer distance then you can select just the right gear to remain just at the most efficient RPM and otherwise ignore the gears until you reach another stretch where you have a different constant speed (and even then, you won't "have" to shift, but you might want to).

In the end, I kind of like the fact that it has a transmission even though I know that it isn't the only solution and I'd rather have seen them spend more time on finding solutions to the power vs. price issue (which is the tack that Zero took), but the specific "faults" listed in that article are not really accurate given the standard practices that should have been explained to them before their review...

Richard230
01 March 2013, 1605
I just returned from a pleasant ride to Alice's Restaurant on my Zero. While there I noted that City Bike is well stocked both in the Restaurant (in the rack in front of the cash register) and in the newspaper rack in front of the gas station. Also the rack across the street next to the Skywood Grocery store contains the magazine.

While there I tried to plug into the outlet box next to the FedEx mailbox and I couldn't get it to work today. So I asked one of the owners if there was another 120 outlet around that I could hook up to while I ate lunch. He said sure, there was one behind the gate next to the adjacent realty office and another one behind the gas station. Photos attached. He also said that they have 240 outlet if I needed it (I don't have the proper plug). Attached is a photo of that outlet, located at the right side of the gas station. Everyone at the Restaurant seems very friendly to elmoto riders. :)

Also attached is a photo of their "Group W" bench, should you need it. ;)

Attached is a photo of the restaurant. The gas station is at the left of the Restaurant and the realty office is to the left of the gas station.

teddillard
01 March 2013, 1609
Yeah, just so we all understand the context of flar's post: http://brammoforum.com/index.php?topic=1908.0

Frankly, I find it fairly amazing that in such a small community a company (and top executive) has no hesitation to be so insulting. Then, I haven't drunk the Brammo Kool Aid. I'll just go back into my garage and be angry I guess... :p

frodus
01 March 2013, 1637
There's just as much koolaid being drank from all sides. Zero.... Brammo....and the DIY community. Everyone has a preference on how to build a machine. Give 10 engineers a spec for a machine and they'll come up with 10 ways to meet that spec. All are right because the solve the problem but not all of the engineers will agree that another is a good solution. Not all of the solutions are cheap... Not all are high performance. But all are designed to meet that base spec.

They just did it differently than Czysz, lightning or Zero or some of the DIY guys have. So what. So far all of the Brammo buyers seem happy with their purchase. Same can be said the zero owners..... as well as those who have built their own.

So yeah, I guess I drank the koolaid. It tastes good and I couldn't be more excited to own an Oregon-made bike that runs on electricity.

teddillard
01 March 2013, 1653
I just remember when we could have good, spirited discussions here and disagree about stuff without being labeled 'haters" and being accused of taking sides. Sorry i don't think everything Brammo (or Zero or anybody else for that matter) has done is god's gift to electric motorcycles. I have the deepest respect for every guy on here who's built a bike, or is trying to, or has tried (due respect Travis). But at the same time there's not one here that I prefer to my own. That doesn't mean that all the guys who get on and raise issues about lipo, PMDC or low(er) voltage systems or decisions I made is a hater.

I've posted several dozen posts on my blog about transmissions and the Empulse, and honestly not one of them is conclusive - I'm trying to work it out and learn. Yet I get labeled a Brammo "hater" because I'm skeptical about the Empulse transmission - in one post.

Once again Brammo is more concerned with their "camp" than promoting electric motorcycles on the whole.

Whatever.

Just call me nostalgic.

More than anything else, it just makes me sad. Even in this microscopically small community, we're polarized.*


*not an electricity joke.

mechanic
01 March 2013, 1656
a problem with the transmission is contrary to the specific instructions I was given on multiple occasions on how to use the transmission.

Brammo said they designed in a traditional clutch and transmission for experienced motorcyclist, guess you cannot use your motorcycle experience however (like the journalist did) you need to follow very specific instructions over multiple occasions- whoopsie...

FYI- don't see any evidence to suggest that anyone here is mad that the Brammo is too good... on the contrary- nice spin though.

frodus
01 March 2013, 1724
So maybe it can be improved the next revision.... Nothing wrong with continual improvement.... Right?

I mean look at motoczysz.... They've learned lessons along the way.....

http://www.youtube.com/watch?v=EDcXm2XQJvQ

I would hate to imagine having to suffer through the judgment of "mechanic" had that happened to Brammo or Zero in front of the general public.

flar
01 March 2013, 1725
Hi Ted,

I don't think that is a good context for my post. I agree there does seem to be some "a real bike has to have these features" thinking that I encounter, but I think the background I gave about myself in my own words in my own post here is a more accurate gauge of where I come from when I came here to join the discussion. A few of us are on a number of forums talking objectively and positively about all aspects of electric design and the various products and I'd like to think that I'm one of them. If you can get over some of the clique mentality with me I'd love to hash out the actual points to be made here since I spend a great deal of my time in discussion with prospective electric motorcycle owners about the strengths and differences and recommendations for *ALL* of the current production bikes (of which I am only really schooled - with first hand experience - on the Zeros and the Brammos). I have no axe to grind, but having been a transmission skeptic I ended up buying an Empulse anyway and I've come to treat it as an interesting novelty. I have found some value in it and I would like to see it eventually become obsolete. While I don't have a great body of knowledge on the various arguments for or against it, I have at least seen a variety of reasons proposed and can bring them up for others to dissect. I am an engineer, but not dealing with anything mechanical.

Keep in mind - I wasn't saying that the transmission comments were wrong, just that they were addressing a concern that I've never seen put forth in any justification of why the Empulse has a transmission. I agree with the analysis, but I think there is more to it that needs to be pointed out and addressed before someone can consider that those design decisions were misguided.

To that end, the article made a number of points that were strong reactions to simple misunderstandings. I'd like to clear up the misunderstandings so that the pros and cons can be put into perspective, not to seed propaganda to try to cover them up or eliminate them. I see quite a bit of knowledge both in that article and on this thread being directed at the wrong assumptions.

More background - when I was first getting into electric motorcycles and the Brammo transmission was being discussed I asked basically that same question about "keeping the bike in a good RPM range" and the question was immediately taken apart by protomech. I learned a lot about electric motors that day and I agree that you don't need a transmission to keep you in "the power band" as was concluded above (and demonstrated with a lot more graphs and facts when I originally asked the question). But, the facts didn't point out "it has no effect whatsoever", they pointed out "there is not enough effect to justify a transmission" and I agree with that. However, that effect was never suggested by anyone at Brammo for why they added the transmission.

They have had (obviously marketing based) comments about riders expecting various attributes on a motorcycle which I've never bought into, and one of their engineers mentioned the "launch power vs. top end speed" issue in a forum posting as the more technical reason behind their choice. I actually mentioned that myself in follow up discussions after my comment about RPM ranges was debunked, and the only counterpoint that was made seems to hinge on using high enough voltage to get enough power to do both with a single drive ratio. I haven't seen anything here address that "grunt vs. top speed" issue. Zero invested in motor power and they didn't quite reach the marketing goals of the Empulse. The best they achieved with the Zero S 8.5 is 0-60 in mid-5s and a top speed of 95 (80 sustained) with a range barely meeting the 100 mile mark. The larger S 11.4 has a less impressive 0-60 and a range better than the Brammo, but still with the same lower top speed of the 8.4. That near-miss achievement wasn't an idle response, they used a huge loan from California to create that state of the art motor. Meanwhile Brammo did manage to hit their marketing goals of 100+ MPH top speed (sustainable I believe) and comfortably over 100 miles of range with a 0-60 in 5 seconds (they never mentioned a target for acceleration but were aiming for being in the same ballpark as ICEs and the number is better than the Zero street bikes). Those were the figures that led them to use a transmission. I asked if the parameters of electric motors will eventually get to those marketing bullet points without a transmission and they claim that economics make it infeasible to do that without a significant price increase. I don't know enough to refute that, but I don't see anything in the analysis of a transmission here that also refutes any of this. We have the example of the under $20K bike that met those goals and it uses a transmission and we have an example of an under $20k bike that didn't use a transmission, used a big loan to develop a beautiful new motor, and yet didn't meet those stated targets.

Personally, the Zero performance figures were good enough for me and if I hadn't test ridden the Empulse I would have bought one on the spot. That isn't to say that I bought the Empulse because it had a transmission or because it met those marketing numbers (it's nice that it does, but it isn't part of my purchasing decision tree), but the fact that they were aiming for those figures and they achieved them with a transmission and there aren't any production bikes that meet them without a transmission (that I'm aware of - I'll gladly admit that I only know about the 2 brands and a few prototypes) speaks for some value in using one and I don't think it is "to keep the bike in the power band".

As far as "wishing it didn't have a transmission", it's not a big deal for me one way or the other. I'm more concerned with chain vs. belt than whether it has a transmission.

flar
01 March 2013, 1746
Brammo said they designed in a traditional clutch and transmission for experienced motorcyclist, guess you cannot use your motorcycle experience however (like the journalist did) you need to follow very specific instructions over multiple occasions- whoopsie...

That seems to be a marketing point for them and I don't buy into it. But, to counter your "need to follow very specific instructions" comment - that is overstating it by a wide margin. It takes less than a minute to make 2 or 3 points that are actually sort of obvious if you know the differences between an electric motor and an ICE. I really wish they'd stop making that "it's what experienced motorcyclists expect" type of comment as my immediate reaction, and I'm sure I'm not alone, is "Ummm... no".

Really the only main instruction is not to use the clutch for stopping and starting. That doesn't mean you can't use it, but it is unnecessary. If you are left to believe that you should use it because that is normal for a bike with a transmission then you will likely run into a lot of ideosyncracies that will annoy you. But it takes about 5 seconds to make that point and then, other than needing to break a habit, the experience is vastly improved.

It would also help to explain the redline and the fact that the engine likes to be revved high. I didn't see any direct quotes in the article, but their "3rd gear in the city" comment leads me to believe that they weren't using the higher revs as much as they should and the bike does love them. The redline is even more unfortunate because the line starts at 6k on the tach, and the lights start blinking around 7k, but the redline is over 8k (which is actually past the end of the tach) and there is nothing wrong with heading on up north of 6 or 7k (other than the lights which warn you of the approaching true limit). Also, the whine gets so high pitched that anyone with an ICE background might instinctively be induced to shift around 3-4k which is much too soon and would tend to lead a rider to believing that the bike needs a lot of shifting.

When I ride in the city I leave it in 1st and never use the clutch and I've never gotten fast enough in the city limits to even have the lights come on.


FYI- don't see any evidence to suggest that anyone here is mad that the Brammo is too good... on the contrary- nice spin though.

I'm not sure I made that comment, but I did get an impression from another forum that the posts here were a hornet's nest. When I came here to read them I thought to myself that it was a lot more subdued than I was led to believe.

Still I do see a lot of dismissiveness in the counterpoints which I find to be a little abrasive - things like "can't discuss it at your level" (lol). I hope I'm not doing the same - I'm really hoping to find more accurate information on the value or lack of value of the transmission. I can certainly speak to whether or not it gets in the way or is a problem to deal with as a rider and I have a fair bit of first hand experience which erased any concerns I had over whether it was "too much fuss" - now I just enjoy the performance of the bike and whether the transmission was really needed is more of an academic curiosity of mine.

flar
01 March 2013, 1803
As we at Brutus have even moved on from the transmission for our use. It worked great when we had somewhat limited power output and also allowed us to quickly test multiple gear ratios. Then again we are not targeting 150mph+. With over 100kw and a gearing for a top speed of 115mph we have enough power to make our 600#+ motorcycles smoke the rear tire.

I think the distinction there vs. the Brammo is that they were aiming for the $8-12k market originally and ended up going to $17-19K. That was about as far as they wanted to push it and still have a 100+MPH capable motorcycle with good launch power. The price listed for the Brutus on the web site is $45K. If Brammo had wanted to target that price range then I believe that they would have gone direct drive. When I asked if the transmission would eventually go away, the "price vs. performance" consideration was the primary reason they gave for why they went with a transmission now (and why they felt it would be a few years before they could do it without a transmission).

Personally, I find a better counter-example to be the $16K Zero that is knocking on their back door with the specs (just under 100MPH, but not sustained, and mid-5s in the 0-60 category are within striking distance of the Empulse figures, but beef up their frame, suspension, and running gear to match the Empulse and you might add enough weight to knock them back a bit).

flar
01 March 2013, 1815
I just remember when we could have good, spirited discussions here and disagree about stuff without being labeled 'haters" and being accused of taking sides. Sorry i don't think everything Brammo (or Zero or anybody else for that matter) has done is god's gift to electric motorcycles.

I'm hoping to continue this thread in that original vein!


Once again Brammo is more concerned with their "camp" than promoting electric motorcycles on the whole.

Most startups do seem to live in an aggressive self-promotion mode, but I hope that you don't assume the same about me as an Empulse owner.

I'm definitely constantly in the position to push the entire industry and concept every time I park my Empulse or even pull up to a stop light (though not much opportunity for in depth discussion there). I'd like to have better ammunition to turn everyone on to the concept and so I hope I can get some decent exchange of ideas here.

mechanic
01 March 2013, 1817
So maybe it can be improved the next revision.... Nothing wrong with continual improvement.... Right?

I mean look at motoczysz.... They've learned lessons along the way.....

http://www.youtube.com/watch?v=EDcXm2XQJvQ

I would hate to imagine having to suffer through the judgment of "mechanic" had that happened to Brammo or Zero in front of the general public.

Good point- But this is NOT about making mistakes: as a (motorcycle) mechanic I have made plenty of mistakes along the way, this is about marketing mistakes (or at the very least, a not ready solution).

Don't remember MotoCzysz trying to sell you that battery as a better solution. (though it looks like it's smoking!)

mechanic
01 March 2013, 1822
But, to counter your "need to follow very specific instructions" comment - that is overstating it by a wide margin.

Umm... That was your quote mate, that is why it is in quotations.

flar
01 March 2013, 1842
Umm... That was your quote mate, that is why it is in quotations.

I never said that you "need" to use specific instructions - that was your word - the instructions help you use it best.

You also said "guess you cannot use your motorcycle experience", but the instructions are quite simple and easily understood by anyone with any experience with an ICE transmission. Some of the recommendations are even roughly equivalent to information you should know about how to use the transmission on 2 different ICE motorcycles (things like best ranges to run the motor, for instance, so you can best figure out which gears to settle into for various modes of riding). Certainly the amount of "experience" one carries forward into using the transmission on the Empulse far outweighs the 2 or 3 parameters you need to understand to modify it. You can easily use it completely oblivious to the differences in ICE vs. electric motor, but you won't enjoy it as much.

Shineysideup
01 March 2013, 2155
Whoa there hoss, we're all friends here, no need to be uncivil. :confused:

Hi moon - I'm assuming this was directed at me since it followed my posts. Didn't mean to be uncivil (don't see where I actually was) but rather, spirited. I am, after all, a Fan Boy, according to another poster.

I guess my tone of impatience was due to reading multiple criticisms by people who obviously haven't actually ridden the Empulse, or who did so in an uninformed manner.

Of course, the condescending know-it-all voice of some posters didn't contribute to the feeling of "we're all friends here." I apologize if I took the bait.

If owning and liking a motorcycle causes me to be labeled a FanBoy and therefore have all my posts dismissed as mere biased, blind, ignorant opinion, great: I can move on. But I actually DO enjoy reading non-abrasive, informed, constructive criticism.

I think Flar's point about the tradeoff between top speed and off-the-line grunt being economically accessible via a transmission is right on.

Of course I'm not nearly so accomplished a DIY'r as most of you on here, but I DID manage build an electric bicycle with 80 miles of range that hauls 400 lbs. up a 30 degree incline. I quickly figured out that with an economic hub motor, I could choose between the torque required by San Francisco's hills, or the speed I desired to whizz along at 25 mph to do my 30 mile commute, but I couldn't have both. Hence a design that ran a standard hub motor mounted outside a hub, and running through a 14-speed Rohloff gear hub worked magic.

THAT's when I came to understand the high utility of transmissions applied to electric motors. Just seat-o-pants knowledge.

Engineering concerns aside, I just LIKE the idea of not having to use much more expensive higher-voltage components, and a much more expensive motor to produce a bike that actually propels me ahead of traffic when pulling away a stop light, something I felt very fearful about when test riding the 2012 Zero. I also very much like not having to run out of useful rpm's when doing a pass on the freeway at 70 mph.

With my background as a machinist, I actually find some charm in a clunky gearbox as giving character to a machine. I grew to like my BMW R1200R for the same reason. And, as Flar reported, I've managed to develop the finesse of throttle control and shifting that the Empulse rewards with snicky-smooth shifts most of the time. So what started out as a thunk, then a clunk, then a tock, has now become a tick. (Your sounds may vary.)

So there you have it. Hope some of you folks can test ride the Empulse some time. It really IS a very beautifully handling machine which will, IME, reward time spent on it with insights that are deeper than any first impressions or paper analyses can yield.

Fanboy over and out.

Hugues
01 March 2013, 2352
....
There are two mechanical tools that can manipulate engine/motor characteristics; overall final drive ratio and transmission ratios.



Overall Final Drive Ratio:

It is rear wheel torque that driver/riders respond to. Most vehicles multiply their engine/motor torque with final drive ratios to increase rear wheel torque/acceleration/performance. (Done poorly like many e-motos and the result is a large rear wheel sprocket, more unsprung mass and more drive inertia and resistance)
....

Thanks for the explanation mechanic, very clear and understandable.

When you say "Done poorly like many e-motos and the result is a large rear wheel sprocket", I surely fall in this category with my 6:1 ratio and 80 tooth on the wheel :eek:

I don't mind to be shown my mistakes, it's my first build. But then i would like to know a better alternative. I chose 6:1 because that was the highest ratio possible. Why i chose the highest ? Because i give priority to 0-60 acceleration over top speed and that ratio gave me around 6-7 seconds acceleration (which is not as good as i initially wanted) and about 120 km/h top speed which is more than enough for my needs (don't plan to ride it on highways, just cruising around). I agree that inertia of a 80 tooth sprocket is higher than 40 or 50 tooth, but for unsprung mass, honestly, it's aluminum and the difference with a 40 or 50 is maybe 1 kg on a fat wheel and tire, it's just peanuts.

So any reason why I would go to a lower ratio ? (or anyone else in the same situation ) and make my 0-60 time go into the "lousy" territory ?

thanks for your feed-back,
(I bought the trantorque nut you told me about by the way, thanks)

teddillard
02 March 2013, 0329
Didn't mean to be uncivil (don't see where I actually was)

Seriously?

Whatever. I could suggest a first post as maybe a sort of benign introduction and greeting but if you want to come into the room swinging, so be it. I live not far from Southie. That's not unusual there. :p

I'd love to ride an Empulse. I've said countless times that I'm delighted they finally are in production so we can see how a transmission actually performs. The problem is, where Brammo once gave me an Enertia to review for a week, I sincerely doubt they'd consider doing that with an Empulse considering their current opinion of my objectivity. That opinion, ironically, is solely based on the fact that I try to remain objective and unprejudiced, especially on the subject of transmissions. Consequently I point out **** that seems to not make sense and seems like BS, which, apparently, gets me labeled a hater. (Funny, I've made a very pointed post dissing Zero's styling and not been called a "hater" by them... ) It doesn't seem to dawn on them that giving a rubber-stamp review on a product doesn't do much for a reviewer's credibility.

And there's the problem.

I'm either dealing with a manufacturer who has bikes to sell and is not inclined to let a reviewer have a bike if they're not going to do a favorable review, or I'm dealing with an owner who's just spent a small fortune for their new bike and isn't going to give me a particularly objective analysis. So yeah. Fanboy. You can say all you want that you built this, tested that, whatever, but it's human nature to believe you made the right decision when you finally plop down cash for -almost any- purchase... nevermind one as irrational as an electric motorcycle. :rolleyes:

I don't much trust journalists, either. I'm happy that the reviews out there have started to surface but everybody has their angle. Many of these guys are coming from the motorcycle industry and are looking for electric motorcycles to mirror gas rides. They don't. The fact that you run the Empulse's gearbox differently than a gas bike proves that more than anything I can say. I once had a guy call me - on the phone - to bitch me out for making what I thought was a funny and irreverent quip about a certain manufacturer who gave him a video and then told him to take it down. It seems the manufacturer took offense to my post, delicate creature that he is, and thought the writer had something to do with it... which would mean that this writer probably wouldn't get a chance to ride this guy's bike ever. Cue Celine Dion.

Frankly, the only opinion I trust other than my own is that of a dealer who carries both brands - but few do, and even then you're faced with particular incentives of that dealer to move one brand over another. I don't care what kind of product you're talking about. So I'm left with finding some guy who's just bought the bike and doesn't mind me trying it out and then telling the few souls who read my blog what I really think of it.

(Yeah, open, lay your cards down and stop your whining call-out. Does Brammo have the balls to get a bike to me to do a detailed review? Would Zero make the same move? I'd love nothing better than to do a head-to-head comparison like I did with the Zero and the Enertia:
http://evmc2.wordpress.com/2010/07/10/brammo-enertia-vs-zero-s-part-1-spec-battle/
...which took me about a week of writing, and got me absolutely nothing in return, not even a note of thanks. But I don't think I'm a big enough fish for either to really care to do it, and I don't think Brammo in particular has the nuts to make it happen. I'd love to be able to decide for myself if the added weight of the transmission is worth it. Something really easy to do... just ride around without using it for a while, compared to riding around using it. Big hairy stinkin' deal. ...and share it in a good, objective and responsible post.)

I'm still hoping that somebody comes back to this thread explaining why a six-speed is "needed" over a 2 or three speed. Why do I hope for that? Not to dump on Brammo as you seem to suggest, but to try to finally decide if my next project might be to go back into my angry garage and try to build what I think would be kind of awesome - a basic dual-range gearbox.

How you can call me and others here armchair engineers when we've all worked so hard on what we've designed and built I'll never understand. But if you stop doing that, I'll stop calling you a Fanboy. So there. :p


I never said that you "need" to use specific instructions - that was your word - the instructions help you use it best.... You also said "guess you cannot use your motorcycle experience"...

The point being the fairly obvious contradiction that Brammo claims they built the bike with a transmission to appeal to traditional motorcycle riders, yet the transmission functions slightly differently, and unexpectedly, than on a traditional gas bike. I'm sure this comment will be read as me hating on Brammo. It's not. It's me observing that electric motorcycles are different and even someone builds a bike with a transmission, it's not going to be the same experience. THAT SIMPLE POINT is what I'm trying to understand, god help me.

lugnut
02 March 2013, 0419
When you say "Done poorly like many e-motos and the result is a large rear wheel sprocket", I surely fall in this category with my 6:1 ratio and 80 tooth on the wheel :eek:

I don't mind to be shown my mistakes, it's my first build. But then i would like to know a better alternative. I chose 6:1 because that was the highest ratio possible. Why i chose the highest ? Because i give priority to 0-60 acceleration over top speed and that ratio gave me around 6-7 seconds acceleration (which is not as good as i initially wanted) and about 120 km/h top speed which is more than enough for my needs (don't plan to ride it on highways, just cruising around). I agree that inertia of a 80 tooth sprocket is higher than 40 or 50 tooth, but for unsprung mass, honestly, it's aluminum and the difference with a 40 or 50 is maybe 1 kg on a fat wheel and tire, it's just peanuts.

So any reason why I would go to a lower ratio ? (or anyone else in the same situation ) and make my 0-60 time go into the "lousy" territory ?



You also have the mass of the chain on that rear sprocket to consider. And my take from his post was to use a double reduction to keep the overall ratio high but the rear sprocket small(er).

Hugues
02 March 2013, 0436
You also have the mass of the chain on that rear sprocket to consider. And my take from his post was to use a double reduction to keep the overall ratio high but the rear sprocket small(er).

good point. Double reduction: i probably don't have enough space for that, but i will think about it once more. But i wonder how many seconds (or fraction of seconds) that would change the 0-60 timing, on a 320 kgs bike that is. Surely important for racing on a lighter bike.

mechanic
02 March 2013, 0830
[QUOTE=Hugues;35908]Thanks for the explanation mechanic, very clear and understandable.

When you say "Done poorly like many e-motos and the result is a large rear wheel sprocket", I surely fall in this category with my 6:1 ratio and 80 tooth on the wheel :eek:

thanks for your feed-back,

Hi Hugues,

First- glad you are not overly defensive (like some) and did not take the "lousy" comment personal, as it is only directed to big rear sprockets not the person.

Sounds like a 6:1 ratio is what you need for your motor torque vs. rear wheel wheel torque/ acceleration (this sounds very reasonable)

Lugnut is correct, a two stage (primary then final) drive would be nicer. Most motorcycle have an approx. 3:1 final drive (14/42). In your case you would require a 2:1 primary reduction (between motor and counter sprocket) along with the traditional 3:1 final reduction = 6:1 overall reduction. This is a machining challenge and may be more of a problem then it's worth in your case but the hardest part (2:1 gear set) should be easily sourced.

As far as space, it will most likely help you as the motor now has some freedom, as it can move (orbitally) around the driven gear (counter sprocket) to the most optimal location.

Of course there are also electric solutions to your 2:1 need but then again these may not be possible at this stage.

lugnut
02 March 2013, 0902
good point. Double reduction: i probably don't have enough space for that, but i will think about it once more. But i wonder how many seconds (or fraction of seconds) that would change the 0-60 timing, on a 320 kgs bike that is. Surely important for racing on a lighter bike.

With a primary reduction, it would allow you to increase your overall ratio and gain wheel torque. You'd maybe lose top speed but you indicate you are o.k. with that. Also, the primary reduction allows you to use a larger front sprocket for the final drive which can benefit the chain. And the motor will cool better at the higher RPM.

Richard230
02 March 2013, 0916
Well, I must say that when I posted excerpts from the City Bike Empulse review article I had no idea the responding comments would become so spirited. It didn't take long for me to realize that I have no qualifications to objectively discuss the engineering merits of transmission vs direct-drive, other than from my personal point of view as a motorcycle rider and consumer.

The reason that I prefer my direct-drive, air-cooled, belt-driven Zero is because I come from the KISS side of the argument. When I first started riding, you had to bring a bucket-load of tools and parts with you to keep your motorcycle running long enough to get to your destination. It didn't take long for me to realize that the more parts you had on a motorcycle, the more things could go wrong and require fixing. For the most part that is no longer true. Modern electronics, superior materials and precision manufacturing typically can deal with complication that would have boggled my mind 50 years ago. But it is hard to shake off years of wanting things as simple as possible so that they are easier to understand and easier to diagnose and repair if they stop working. It is really hard to teach an old dog new tricks.

Also, in my case, I don't care about acceleration or top speed. If my motorcycle will run at a steady 80 mph and will keep ahead of most cars away from a stop light, then all I care about is range. Not having a transmission means that the additional space can be used for more batteries, or the motorcycle can be made smaller and lighter - which are always a good thing. I note that many BMW owners are now complaining about the new models becoming too large and heavy for anyone to feel like they are really in control (especially as these owners age) and many riders are having more fun going lighter and slower and are wishing BMW would do the same. (As an example, the new water/air-cooled BMW R1200GS weighs 25 pounds more than the previous model, which itself was no lightweight - especially when taken off-road.)

I really think that having both Brammo and Zero in the production EV market is a very good thing. It gives consumers a choice that you do not usually get now-a-days from the different IC brands. Do you want a transmission and the ability to shift between gears, or do you want to just turn the throttle and go, without as much involvement with your vehicle? Let the consumer decide. I would argue that Zero should ultimately have the greater consumer base as that is the example in the auto industry. Very few auto consumers want a manual transmission anymore and even fewer know how to drive a manual transmission car. If my first motor scooter used an "automatic" transmission (instead of a 3-speed twist-grip) like the new scooters do (including BMW's new IC scooter), I would never have learned how to ride a motorcycle. It took me months to master shifting well enough so that I no longer had to think about what I was doing when I was riding and that was a struggle that I would probably have liked to forgo. (The fact that the shifting and clutch cables regularly broke didn't help matters any.)

I believe that the market for new riders, which will likely make up the majority of elmoto sales in the future, are more likely to want to purchase a motorcycle that does not have a clutch, neutral or a transmission. Which design is better will ultimately be left up to the consumer - in my opinion. But I certainly have no objection to seeing the two sides of this engineering thought battle it out. It should continue to be very entertaining. :)

teddillard
02 March 2013, 1200
Well, I must say that when I posted excerpts from the City Bike Empulse review article I had no idea the responding comments would become so spirited.

...yeah. Riiiight. I believe you. :rolleyes:

Shineysideup
02 March 2013, 1455
...yeah. Riiiight. I believe you. :rolleyes:

As a mentor of mine once said, "Men want to be always right. Right. Right. Dead right."

I'll choose a good ride today, instead.:D

teddillard
02 March 2013, 1635
As a mentor of mine once said, "Men want to be always right. Right. Right. Dead right."

I'll choose a good ride today, instead.:D

Sorry if I'm a little dense. WTF is that supposed to mean?

Hope you had a good ride.

flar
03 March 2013, 0017
The point being the fairly obvious contradiction that Brammo claims they built the bike with a transmission to appeal to traditional motorcycle riders, yet the transmission functions slightly differently, and unexpectedly, than on a traditional gas bike. I'm sure this comment will be read as me hating on Brammo. It's not. It's me observing that electric motorcycles are different and even someone builds a bike with a transmission, it's not going to be the same experience. THAT SIMPLE POINT is what I'm trying to understand, god help me.

I guess I can't speak for Brammo, but I'll point out that they use that as a "catch-all" in their marketing when talking about many properties of the bike. My guess is that it was their starting philosophy on building the bike. (Commercial Production) Electric motorcycles all had compromises in areas that traditional motorcyclists might balk at - and power and top speed loomed large in the list of compromises (at least in the sub-$20k market). Continuing on with that guess I'd say that it became a theme that was brought up during most of the design decisions. These assumptions are coming more from my past experiences in product development in other areas where early on someone states that "we need to build a product that is X" and as you go along, "X" becomes part of the genetics of most of your reasoning even if it doesn't exclusively justify any of the decisions. Later, in the marketing phase, the marketing team tends to run with "X" in all of their descriptions of the value of the product and most employees stick to talking points approved by the marketing team when speaking to press and in public forums. That seems to be happening here, but you need to dig under that to really understand the relevant points. To that end, I've seen them mention the various aspects of the transmission as intending to appeal to a traditional motorcyclist (their overall marketing theme), but when you get into a technical discussion with the engineers in a forum they give actual engineering reasons instead.

With respect to the article, I can see that if they were given the motorcycle and told "it has a transmission which works just like any motorcycle's" and that was all they were told then they'd end up running into most of those same disappointments. But, is "you should keep the engine at the higher RPMs" any different than an instruction you'd give to a journalist that had exclusively reviewed and ridden Harleys when you instead handed them a Ninja 250? If you didn't at least make sure that that reviewer was aware that the tiny engine needed RPMs to perform then you'd run the risk that they'd come back with a review that said that the bike didn't develop enough power to even ride down the street at regular traffic speeds "even when I ran it up to 4 or 5 thousand RPMs". Oops.

So, yes, oops if that was all they were told because just like 2 ICE bikes may need different attitudes towards RPMs to get an accurate feel for their performance, these bikes also have their own RPM preferences. Such a simple "it's just like you are expecting" instruction wouldn't even pass my test for what I'd tell a friend if I loaned them my BMW and wanted them to enjoy riding it. "Is this your first time on a BMW R bike? OK, then ..."

With respect to their disappointment that dumping the clutch wouldn't help them do a wheelie - yes, that's an area where this bike has different properties as well. I'm not sure if there are any gas bikes with small enough engines and flywheels to also not respond to that tactic, but what struck me more about that comment in their review was that they blamed the motor controller for babying them when it was simply a matter of physics and electric motors. I don't think "let's make a huge engine with huge rotating mass so that it responds to dumping the clutch with a strong lurch" would have been a smart move even if it may have replicated more of the ICE experience.

In any of these matters I don't think "is familiar to ICE riders" really means "is indistinguishable from an ICE" - it means "erase as many of the compromise shortcomings that electric motorcycles have had". When applied to "should it have a transmission or not" then I think the biggest factor was more the "can we get both launch power and top speed" than "are they going to miss a clutch". Once they determined that economics recommended a transmission for removing the "launch power vs. top speed" compromise then I'm sure "familiar to ICE riders" came up again as a supporting factor for 6 speeds, but I don't think they would have made that decision solely on familiarity grounds. Going past product development, when it came time to announce the bike and feed statements to the press, then I'm sure the marketing team put more stake in the "familiarity" language than was really true to the fundamental design decisions.

Another analogy I'll point out here is that when Steve Jobs announced the "retina display" I did some serious eye rolling. As a graphics engineer I could give a ton of reasons why the high resolution was a good thing, but to listen to Steve Jobs go on and on about it, combined with the name "Retina display", as if they had somehow transcended the laws of physics really galled me. Still, I could separate the technical from the marketing and I was only really annoyed by the marketing message. Similarly, while I sometimes roll my eyes at the use of the "familiar to ICE riders" messaging, I do have a feel for the technology and I think there is merit to it even if the glossy print reasoning doesn't really explain it.

So, I guess I should revise my earlier statements. If you were simply poking fun at their marketing message then I hear you and I agree that the reviewer's experience contradicts the "familiarity" marketing message in its most literally interpreted form and I recognize the schadenfreude. But, taking a marketing message at face value and robotically interpreting it in its most literal form is a fairly weak discussion point. I guess what I was responding to was a sense that the decision itself to have a transmission at all was being mocked, and I think it deserves a bit more than "these reviewers didn't like it because it didn't act just like an ICE with a transmission which was the words that came out of the manufacturer's mouth, therefore transmissions suck, we win, qed". Umm, no. I agree it isn't "the same as an ICE with a transmission", but it isn't really all that different. If you want to take them literally to mock their marketing, I'm good with that. If you want to question the value of the transmission based on that progression then I think that ignores the actual values it does provide.

flar
03 March 2013, 0038
One more point about "having a transmission" and how it fits in with the messaging about designing the bike to appeal to existing riders - I found this article:

http://plugbike.com/2010/07/15/introducing-a-trio-of-brammo-empulse-sportbike-prototypes/

In the first paragraph the writer talks about "Brammo’s answer to many of the complaints motorcycle riders have about the current production electric motorcycles" which is loosely reflected in the tone of the quoted press release, but I think that was the tone that eventually grew into the current marketing messages about "we did this or that for familiarity".

The important thing to note - the prototype bike (pictured at the top) that started this whole effort was originally going to be direct drive. The transmission came late in the game and while you could find some engineers talking about not getting the power/top speed they were looking for at that price without the transmission, that makes a weak marketing message. "A transmission is familiar to motorcycle riders" covers for "we couldn't get motors in this price category powerful enough for both targets". In some sense you could chart it:

Motorcyclists want to compete with ICE motorcycles in the target category on low end power and top speed.
We need a transmission in order to be competitive in both specs with ICE motorcycles in the target range.
Thus...
Motorcyclists expect a transmission on this bike.
;)

flar
03 March 2013, 0116
OK, the issue of 6 gears vs. 2 or 3.

I'll start with an anecdote. One of my favorite cars was a twin turbo V6 that had an amazingly wide and flat powerband. It had enough power that I'd be passing all of the cars on mountain climbs in top gear. My typical driving technique tended to be "1st, 2nd, 6th". (6th? Really? Yes, 6 gears on a car...) Most of the time 3rd, 4th, and 5th were irrelevant. Why would they make a car so strong and with such a flat powerband with 6 gears? Well, I'd take that same car up into the twisty roads in the mountains and then I'd see a lot of use of the other 3 gears. With a peaky motor I might have had to constantly row all of those gears, but with this motor I could leave it in one gear for 10-15 miles at a time, then I'd come to a crossroads and turn onto another road and might choose a different gear for that road. It could have easily done either road in either gear, but this gear was better for that road and that gear was better for this other stretch. I could have also constantly rowed the gears to completely maximize my performance (and might have done so on the track), but generally I could just enjoy the drive at a really spirited pace by choosing a gear that was just tall enough to not need to shift up (whether it be due to red line or due to not wanting to make any more than that much racket), and no taller. Yes, it had enough power to do it in the next taller gear, but the mechanical advantage would have meant slightly less performance (even when both gears were in the meat of the powerband) and more gas used.

The Empulse is just in that same boat. You don't need to row the gears. I suppose you could if you really wanted to fool yourself into thinking you were eeking out every last bit of performance and I'm sure some riders might be good enough to do just that on the track, but mere mortals probably won't really get much from constant shifting. But, if you only had 2 (or 3) gears to choose from then you'd have only 2 choices of mechanical advantage to amplify your power. If low gear was not high enough then you'd have to use high gear and it would have radically less performance. If the road was borderline then you could either just live the entire way with the radically reduced performance (mechanical advantage) of the higher gear, or you could mind the tach and constantly switch back and forth, but that would be more bother. Also, I don't know, but would swapping between 2 gears be more of a disruption than a 6-speed single gear snick? In the end, I can do the same thing as I did with that car - choose a gear for the current situation that maximizes the available strength of the motor due to the chosen mechanical advantage while staying below redline or staying close to the meat of the efficiency curve and then enjoy an extended period of riding with excellent situational power and no worrying about the shifter.

If you ignore the twisties then with just city and highway I think I'd want at least 3 gears or I'd choose to live with a marginal top speed. Granted 100+ is not a big goal of mine, but it was for Brammo. I wouldn't want 1st to be any taller than it is and it can barely reach 60 at redline so you'd need another gear for the highway. If it were a gear that reaches 100 then I would feel cheated in doing a 60-70 passing maneuver (note - I guess I should at least try, but my impression is that I'd want as much power as I could get for that situation and 100MPH doesn't help me maximize that). So, if it were just city and highway and I wanted to live with a top speed of 80-90 then I think 2 gears might be enough, but if I wanted city+hwy+100MPH then at least 3.

(And then throw in twisties and I'll gladly welcome 6.)

However, with a much stronger motor then I'm sure I could get plenty of power for any need with a single gear across all speeds. The question is - how close are we to motors that can do that on a mid-teen$ production bike? I think the '13 Zero's come close enough for me, but I'm probably a little more mellow than most riders. I don't think the motor on the Empulse would be sporting enough for me if I locked it in 6th gear. I definitely want its 1st gear for stop light launches (maybe not need, but definitely really like). I'd have to do more experiments to see just how much specific gear choices really matter in the twisties, but combining my first 1100 miles of experience on the Brammo (OK, really only about 3 or 4 moutain twisty runs) with my experience from that car, I think it is more than just a hunch that the 6 gears are useful.

teddillard
03 March 2013, 0353
A lot of speculation there... On Brammo's claim that they went with a transmission to appeal to ICE riders from the start? Sorry, that's not how that went. There was no "We want to give traditional motorcyclists a familiar ride.", in fact it was all about the new generation of motorcycling. (This blather even extended to the Best Buy fiasco... they were targeting an "all new market".) They, as I think you pointed out somewhere in there, started the design as a single-speed direct drive as are most electric motorcycles. The line that they went with a six-speed transmission to appeal to traditional riders came a few months after the official announcement that the new design would have the tranny - long after the Best Buy deal fell through and they had to start searching for a dealer network. I'm not sure when the Harley relationship started up (or even if it's still in place) but I found this post (http://www.elmoto.net/showthread.php?1485-Brammo-at-Harley-Davidson-Dealerships). Maybe they had a goal in the "DNA" of the design to do so, but didn't originally include shifting.

My distinct memory of how this went was that they delayed the release of the Empulse for no publicly stated reason. The insiders I spoke to said they were overheating motors. Sorry, I can't remember which motor they were running at the time. The comment specifically to me was, "The only rider who doesn't smoke the motor in the Empulse is Brian." It was from someone who I believed but obviously can't identify.

Then they released the transmission news. I remember this so distinctly because at the time I was trying to understand the issue and it dawned on me that running a transmission on a smaller motor allows you to keep that motor cooler. A big lightbulb went on, and we discussed it here at long length. (Up until then, running a tranny to me was to simply go faster, it hadn't occurred to me that it could also be a solution to overheating - sort of a band-aid, but a solution none-the-less.) Here was the release: http://evmc2.wordpress.com/2011/05/04/update-from-brammo-empulse-production-transmissions/

Again, I honestly couldn't give a crap about their marketing message or anything else. I'm trying to understand how to build a better bike with an electric drivetrain.

As far as speculation about whether a 6 speed is better, I'm not going to hash that out, especially in a speculative way, though your speculation based on what riding you've done is interesting. Please do a search here for "transmission" and read up on the probably several years worth of work we've all done here on the subject and available motor choices. I just found this thread (http://www.elmoto.net/showthread.php?1245-does-Brammo-not-really-understand-el-Moto%92s), specifically on the Brammo release and the two-speed concept if you can get past the title.

I was interested in it because two members stated that there had been some explanation somewhere by Brammo (I assume) that a 2-speed was not possible and that a 6-speed was necessary. I'd like to read that, I'm hoping I can learn something.

(edit: Here's a thread on Brammo around that time, talking about cooling etc. http://www.elmoto.net/showthread.php?1238-Empulse-RR-not-sure-if-this-is-a-repost-LOOKING-GOOD!!)

Ken Will
03 March 2013, 0639
A few points to ponder:

"Engineering" makes a great product, but, "Marketing" sells the product.
One of my favorite books is "The Soul of a New Machine". It is about the conflicts between Engineering and Marketing at "Data General" as they are developing and trying to sell a evolutionarily new computer.

Most of the general population, ( i.e. potential customers), know a lot less about electric Motorcycles than anyone here. There for Propaganda is more important than Data logic.

Six selectable gear ratios, make the bike more of a one size fits all type product. The dealers don't have to stock one model for city use and a different model for highway use etc.

"Six Speed Transmission" triggers the same brain cells as gold necklaces and other "Bling". When those specific brain cells are triggered, it is easier to sell the product!

flar
03 March 2013, 0735
Again, I honestly couldn't give a crap about their marketing message or anything else. I'm trying to understand how to build a better bike with an electric drivetrain.


That's fine as I don't care much about their marketing message either. But, some of the comments early on in this thread were comparing the results seen in that article with the marketing message and I'm only covering it here to point out that it is, in fact, a marketing message and not the technical reason why they used a transmission.

For example, BrammoBrian mentioning torque multiplication as a factor in this post (http://brammoforum.com/index.php?topic=1814.msg13913#msg13913).
Later in the same thread he mentioned cost in this post (http://brammoforum.com/index.php?topic=1814.msg13919#msg13919).

Those aren't "because a rider expects there to be a shift lever and a clutch" reasons and I don't want the discussion to bog down in those.


As far as speculation about whether a 6 speed is better, I'm not going to hash that out, especially in a speculative way, though your speculation based on what riding you've done is interesting. Please do a search here for "transmission" and read up on the probably several years worth of work we've all done here on the subject and available motor choices. I just found this thread (http://www.elmoto.net/showthread.php?1245-does-Brammo-not-really-understand-el-Moto%92s), specifically on the Brammo release and the two-speed concept if you can get past the title.

I read through the thread you forwarded, but it seemed to focus more on how to make the best use of the motors on hand (and didn't really state any performance targets to compare) and wasn't directly focused on cost. When I pressed Brammo for information on what it would take to get to the point where a transmission wasn't needed any more the reply was focused on cost. But, the discussion on the thread here seemed to ignore cost except for 2 things. First was that there was a lot of discussion on pushing the standard motors that most people were considering past their stated limits and how tolerant they were with that. It's not directly about cost, but the impression I got was that if you have to push the motor you are looking at then you are trying to avoid paying more for the right tool. The second was that I saw someone mention that instead of the various suggestions for pushing their chosen motor to its limits they could upgrade to a more expensive ($5000) motor, but they wanted to avoid that. I didn't see any mention in there of what 0-60 or top speed they were looking to get, though. Again, I think that's where Brammo was - how to produce these performance figures in a bike that could be manufactured and sold for under $20k - and the transmission was their key to that formula. (Also, that formula includes a lot of high end components to make it handle as well as it accelerates, so the motor and controller cost are even more constrained.)

Much of the discussion I've seen in terms of whether a transmission is needed seems to focus on "you can do this and then it has plenty of power" and I haven't seen much analysis of what that costs. Certainly Tesla can do it in a $50-$100K car. It also looks like Brutus is planning to do it in a $45K bike. Until this year, neither Zero nor Brammo was managing to do it in a production motorcycle that made it to market for mid-teen$. This year Zero has gotten in the ballpark with a new motor - I'm excited by that. But, I think Brammo got just a little bit further in terms of performance with a transmission instead. I await some reviews with hard numbers to find out how they compare, though.


I was interested in it because two members stated that there had been some explanation somewhere by Brammo (I assume) that a 2-speed was not possible and that a 6-speed was necessary. I'd like to read that, I'm hoping I can learn something.

I don't think I've seen anyone from Brammo claiming that, but I did see some speculation on various forum threads discussing "why 6 speeds" that mentioned that Tesla had had some trouble with a 2-speed gearbox on the Roadster that caused them to go back to the drawing board and return with a higher power motor instead.

jonescg
03 March 2013, 0756
Yeah, I can see how an underpowered motor can be easily remedied with a transmission (2, 3, or 10 speed) if the alternative is to spend another squillion bucks on a more appropriately sized motor.

If you released a bike with a motor which would smoke if it didn't have a tranny, do you tell the world that it was undersized, and that's why you installed a gearbox? Or would you say you wanted motorcyclists to enjoy the sensation of belting through a gearbox? Given Brammo's success at the track has been on single speed bikes, it does start to raise questions about the need, and justifications for the gearbox.

However, designing or sourcing a bigger motor for the job isn't cheap, and I can totally see how adding a box is a perfectly viable option from an engineering perspective.

teddillard
03 March 2013, 0937
I don't think I've seen anyone from Brammo claiming that...

Neither do I, at least that I can recall. That's why my interest in these two statements:


Arrgh. The reason for 6 speeds was because 2 or 3 won't work. ...

and


...
Somewhere Brammo has hinted at or stated that this is one of many reason they have 6 gears. I'll post if I find the thread/post

As far as your comment:
I read through the thread you forwarded ....

...you really need to look at all of the threads we've hashed out to understand what's being said here. The thread I forwarded is only one of maybe a dozen, and all of them more than 20 pages long. Hell. Searching "transmissions" alone gets you over 199 pages of results here. I had an obsessive fixation on motor cooling as well, where I talked about transmissions too. :D

For one thing, your comment about cost? It was a central issue, revisited repeatedly in almost every thread, especially since an off-the-shelf any-speed transmission is well into, or more, than the cost of a motor.


... I can totally see how adding a box is a perfectly viable option from an engineering perspective.

Except for the weight gain, which is reflected by the difference between the 2013 Zero and the Empulse. Which brings us full circle back to the beginning of the transmission discussion.

podolefsky
03 March 2013, 1001
Hey...fellas...peace.

Transmissions are like tax cuts - everyone has an opinion, some more right than others, but if you think you have all the answers you are definitely wrong.

teddillard
03 March 2013, 1023
What'd I say? I thought we were being nice! :p Besides. My opinion is that I have no idea what the answer is. And I'm RIGHT dammit. :D

Skeezmour
03 March 2013, 1030
Heck ya your right! No wait I'M RIGHT! No No wait.....Oh heck I need a drink :)

teddillard
03 March 2013, 1110
...another squillion bucks...

Is that Australian for eleventy-million? :rolleyes:

Shineysideup
03 March 2013, 1344
I‘d like to explain, er, or since I’ve been deemed The Uncivil One, I’d like to elaborate on What The **** my quote on being “right, right, dead right” meant. I don’t for a moment think of anyone here as dense; rather it was my comment that was elliptical; I’ll elaborate:

It appears to me that there is a DRIVE to be right that is prevalent on this board, acknowledged nicely by the humor in the above posts.

In my experience, men in particular, especially those of us educated in so-called First World countries, have been thoroughly trained to identify our selves, or least our egos, with being right. While there may be nothing wrong with being accurate in our perceptions and conclusions, but the NEED to be right all the time, robs me of the spontaneity and joy of learning from mistakes and appreciating others’ viewpoints as something novel, even wondrous, rather than that of an adversary that must either be dismissed or vanquished with “whatever” comments, straw-man arguments, red herrings, name-calling, stridently defended positions, etc., that have become all-too-common in our political discourse. This compulsion to be right, in order to feel we have value as human beings, robs me of rich relationships and limits the scope of my knowledge.

(I ended up taking my being called a FanBoy as a compliment, since I’m pushing 70 years old!)

A really cool girlfriend asked me one time if I’d rather be right or happy. Back then, I thought being right WAS being happy! She left. I learned something.

Back to the regularly scheduled programming:

Aside from the hypothetical considerations about marketing and decision making around the Empulse’s transmission, I find the gearbox to prove very useful, exactly because of the kind of granularity that Flar delineated above.

Part of my daily commute consists of a dangerous series of 4 lane merges on a freeway, with quite a bit of speed differential between each lane, and not a great deal of distance to accomplish the merges. I find the ability to start at around 40 mph in first gear at the efficient 5K rpm motor speed and then accelerate hard to the power peak at 6K, powershift to the next gear and repeat, is of genuine real-world benefit. Sure, if I’d spent somewhere north of $40K, I could have the same capability without a transmission. Heck, as expensive as the Empulse is, I doubt I could build a comparable machine for less as a DIY project. But I could be wrong. And I digress.

I also really appreciate the ability to slam the tranny down through the gears when taking my long, downhill exit, going from 75 mph to 15 mph before applying the brakes. The regen in 1st gear supplies more “engine braking” than the big twin of my R1200R. So, yes, for this person, feeling like a traditional motorcycle with multiple gears is welcome and practical, regardless of any marketing ploys that may have corrupted my assessment before the actual riding of the bike. The transmission contributes to making ownership of an electric motorcycle eminently rational AND fun, so much so that I got rid of my ICE car.

As for being right, I also like a little friendly stoplight competition from time to time. So the torque multiplier by 1st gear (beau-coup [eleventy million] Nm’s to rear tire) is also, perhaps not so strictly rational, but is a heckua lotta fun.

By the way, I’d LOVE to ride the Empulse up and down the 7.6 miles and 4600 ft. climb of Mt. Washington. That would be fun, tranny and all!

teddillard
03 March 2013, 1555
...By the way, I’d LOVE to ride the Empulse up and down the 7.6 miles and 4600 ft. climb of Mt. Washington. That would be fun, tranny and all!

Well HELL. NOW you're talkin'. :D

I was taught that the most important thing is forming a good question... considering that there really are no answers. :rolleyes: Noah knows what I'm talkin' bout. So nobody is really right.

...which is what I found so annoying about a few Brammotians claiming that I was poo-pooing the Empulse transmission. How could I poo-poo something when I hadn't even decided for myself? Which led me to poo-poo Brammo "owner's" attitudes (at the time there were no Brammo Empulse owners.)

I'd say we all want to invest our time and money on a build and have it work well... be right. However, since I'm on my third bike, and 4th version of my second bike, part of the fun is re-doing what I got wrong. On the transmission debate though, I really would rather buy more batteries than be wrong about putting a tranny in. :o Which is why the angry garage thing made me laugh so hard. If I'm right, I got nothing to go out to my garage and fuss with on a Saturday morning...

Thanks for the observations... very interesting stuff to hear.

Electric Cowboy
03 March 2013, 1653
Omg what a long drawn out thread.... People so hostile.

My 2 cents on the matter... I think I have a qualifying opinion. Is that for the current speeds a 2 speed transmission would be optimal if you really really needed one.... Or you could just have a more powerful motor in the same space with ceramic bearings good cooling and higher voltage, and less to break.

Just saying, if my over 20k miles of electric bike riding and racing counts that is.

Sent from my HTC VLE_U using Tapatalk 2

podolefsky
03 March 2013, 1825
Or you could just have a more powerful motor in the same space with ceramic bearings good cooling and higher voltage, and less to break.

Ceramic bearings are bullsh!t and higher voltage won't get you anything you can't get with higher current.

See how that worked? I just slammed EC because I could. Who cares what his point actually was...I have over 2700 posts, he has 50, so I'm 54 times more right than he is. It's just math.

(EC, just kidding...)

Electric Cowboy
03 March 2013, 1834
Lmfao!!! Amen.

Sent from my HTC VLE_U using Tapatalk 2

jazclrint
03 March 2013, 2257
Now that things seemed to have settled down. Ted, my comment about the 2 or 3 speeds not working was based on some article written a couple of years back. I swear James Parker wrote a piece about why a two or 3 speed transmission would not work a motorcycle application, but I have yet to find it. What I took away was that the jumps were too big for the top speed and acceleration performance you were looking for. But if you put them close enough to work the advantage was next to nothing. Clearly old cars had three speed transmissions, so obviously they work. But as Brain of Brammo has said they needed to keep the ratios close to keep motor speed easier to control. I did not intend to start another transmission thread, as it is a dead horse. My frustration is that Brammo has been very clear about why they have used a six speed and I get frustrated with reviews where it seems pretty apparent that while the review was fair enough, they didn't bother to actually do any home work about the new thing they were testing and made seemingly ignorant comment. Similar to when people review a Zero and talk about how they used to have bicycle components. That was years ago. Or maybe I'm just mad they get paid to say dumb things and I don't. :p

jazclrint
03 March 2013, 2313
Found it! But Parker didn't write it, he was quoted: http://www.motorcycle-usa.com/750/10144/Motorcycle-Article/Brammo-Shifts-Gears.aspx

Actually still very relevant and great peice for something from 2011.

jonescg
03 March 2013, 2325
Is that Australian for eleventy-million? :rolleyes:

Our alternative is a metric ****-ton. Slightly less than an imperial ****-ton, but far more convenient unit than dollars.


Except for the weight gain, which is reflected by the difference between the 2013 Zero and the Empulse. Which brings us full circle back to the beginning of the transmission discussion.

Yeah, like it or not this has turned into a tranny-thread.

If I'm not mistaken, the thread is really about a journo who tried the Brammo and didn't like it's gearbox.

I didn't like the Triumph sprint's gearbox either...

jazclrint
03 March 2013, 2338
Along that line jonescg, I heard a customer who bought a Buell EBR1190RS called Erik and asked what the other 3 gears were for. :D

flar
04 March 2013, 0115
...you really need to look at all of the threads we've hashed out to understand what's being said here. The thread I forwarded is only one of maybe a dozen, and all of them more than 20 pages long. Hell. Searching "transmissions" alone gets you over 199 pages of results here. I had an obsessive fixation on motor cooling as well, where I talked about transmissions too. :D

For one thing, your comment about cost? It was a central issue, revisited repeatedly in almost every thread, especially since an off-the-shelf any-speed transmission is well into, or more, than the cost of a motor.

I think that is getting a bit beyond my intention to contribute to the discussion. I am not well schooled in the capabilities of the electric motor and I don't want to take the time to do that. I have an academic curiosity as to where the discussion leads, but not enough of one to jump in the fray and become an expert.

Primarily I wanted to point out that comments that I saw here that "Brammo said the transmission was a win because it made the Empulse feel more like an ICE" is a sort of marketing-driven red herring and that the technical reasons given when owners inquired of engineers were more concrete. I'm not here to be the point contact for those reasons, I just wanted to point out that the points being made were aimed at the wrong reasons from what I've seen. It may actually be part of the reason, but probably not the driving technical reason.

I've also seen protomech engage in some more technical debate over on the brammo forum so the points were being challenged there as well. Hopefully some reasonable people who are already schooled in many of the issues will meet to talk it through and I'll watch from the sidelines. A couple of people from this forum introduced themselves over there recently and were well received. Brian feels a bit abused from previous experience here that I was not a witness to and so he doesn't come here to discuss it any more. I'm sure he'd love to talk these technical details with someone who is genuinely "still trying to figure it out", but conversations that start with "you shouldn't have done that and I know why" are probably not going to garner his attention - he has a day job that is pretty hectic these days. ;)

For my own part, I'm not here to push "I bought the Empulse so its suspension is king". In actual fact I would have rather had a direct drive motorcycle - mainly for Richard's reasons of simplicity, not because I know anything about whether it should need one or not. But I fell in love with the chassis of the Empulse and I do love its performance. Perhaps the transmission is responsible for that performance, perhaps it was unnecessary. I just know it does perform and I didn't have to build it myself and I am finding it fun to play with the transmission despite not really wanting it. One of these days I may play a bit more with it to try to come up with some more objective observations about having it, but I think that the main justifications will end up being what they could have accomplished for a target price range and no amount of experiments I might do as an owner/rider will really speak to that tradeoff - that would require "building it and comparing"...

flar
04 March 2013, 0139
Found it! But Parker didn't write it, he was quoted: http://www.motorcycle-usa.com/750/10144/Motorcycle-Article/Brammo-Shifts-Gears.aspx

Actually still very relevant and great peice for something from 2011.

I loved reading that - it discusses both the technical aspects and also the "familiarity" and "parity with ICE" non-technical issues and shows how they inter-relate. There is a comment in there from Brammo about avid motorcyclists wanting a transmission, but it is brought up when they had already identified the technical need for it to achieve their performance goals.

A couple of things that my limited knowledge doesn't know how well they translate into the current product and discussions - they showed a DC motor graph and talked about voltage limitations for brushes. But, the Empulse uses a brushless PMAC motor. Do those factors affect the basic graphs or performance profiles that they were discussing in that article? Do AC and DC have similar graphs? Is there another voltage limiting (or complicating) factor even if you don't have brushes?

teddillard
04 March 2013, 0310
Found it! But Parker didn't write it, he was quoted: http://www.motorcycle-usa.com/750/10144/Motorcycle-Article/Brammo-Shifts-Gears.aspx

Actually still very relevant and great peice for something from 2011.

Oh, OK. I read that when it came out too. Thanks for digging it up.

Funny. Yeah, so some fairly elaborate speculation by a journalist based on information from what, three sources? (lol Lennon and Charles are both guys who are friends of Adam - remotecontact - though certainly very knowledgeable even they'd say they're far from the final word on transmissions on motorcycles. You want a tranny in a shopping cart tho, Charles is your man. Check out his instructable on fabrication, it's really great - if there are any builders still reading this thread: http://evmc2.wordpress.com/2012/12/30/how-to-build-your-everything-really-really-fast-instructable/)

We've covered all that speculation and modeling here, and more. It's far from conclusive.

I still want someone to do a really simple test that I can't do on my transmission-less bike. Take a backpack with 40 pounds in it, and put it on. Accelerate with your transmission through the gears. (This is your "transmission model".) Then lose the backpack (shedding the 40 pounds that the tranny costs you), pick the gear that represents what you'd run if you only had fixed gearing, and do the same run. (This would be your "non-transmission" model.) If you're unsure about which gear would be "best", then try a few.

I'll buy the first Empulse owner a beer who does this test will some good data. :rolleyes:

We could see actual load data. Speed/acceleration data. Range data. Stuff that's not speculation, that we could then use to model bigger and smaller motors, batteries, stuff like that. I've said from my very first post on the subject, this really isn't rocket science, we have MATHs.


I think that is getting a bit beyond my intention to contribute to the discussion....

Right. My point being, and to say it again, I'm not going to re-hash that discussion... (or didn't want to anyway), since it's all been done here. Eleventy million posts worth of it, and if you're interested you can see it for yourself and come to your own conclusions.


...My frustration is that Brammo has been very clear about why they have used a six speed...

Funny. MY frustration is that IMO they haven't at all. There's a huge disconnect, as I've pointed out repeatedly, between what we've seen and what they're now saying, which I think is driven by their sales and marketing and not their engineering, a subject we've also beaten to death here. The frustrating part is that I'm trying to learn, and what people are taking at face value from Brammo I'm not buying.

So yeah. Back to the reviews. Sitting down now. :p

billmi
04 March 2013, 0720
In that article, Bramscher laid out the reasons I suspected from day 1 that Brammo went with the 6 speed transmissions, and certainly the reasons I'd consider using one if I were designing a production bike. They're building a bike to compete with gas bikes that have top speeds over 100mph and great acceleration. Never mind that there's no legal use for going 120 off of a race track. Even for a customer that's going to be buying a "manly" motorcycle just to ride across town and never on the freeway, if they look at a gas bike that has a top speed of 120, and an electric that has a top speed of 80, a lot of customers would shy away from the electric, because it is "weaker" than the gas bike.


you could either have a bike that went 110 or 120 mph and had acceleration that was just OK, or you could have trouble keeping the front end down, but you'd only go 80 or 90

While that's not to say it's impossible to get both the top speed and acceleration at a single gear ratio, I expect that adding a transmission makes it possible to achieve both while maintaining a price point that is more likely to work in the traditional motorcycle market. I don't think there are very many people willing to pony up the price for a Lightning.

Then comes the next issue. Do you invent your new transmission and undertake all the design and tooling costs to build, debug and mass produce it, or do you take an off the shelf transmission that works but has more gears than you need to reach your goals because it was originally designed for ICE bikes that need more gears. Of the 2-speed tranny, Bramscher said:


it wasn't readily available, so you were talking about a five million-dollar investment.

All seems pretty logical to me.

And sure, if I were writing marketing copy, I'd add some spin about the traditional transmission appealing to experienced riders, since that's the market sector being targeted.

Richard230
04 March 2013, 0854
I agree with Billmi's comments about why Brammo selected a 6-speed transmission for the Empulse. At least those are the same "arguments" that I heard directly from Bramscher when I spoke with him for 20 minutes two years ago about the change in direction that they were making with the Empulse design (a transmission, a higher price and a much longer wait for me to get one - my real irritation). While I could understand his reasoning and figured that it was his money and his company and he could do whatever he wanted with it, I still wasn't happy because it looked like my long wait to buy a new Empulse was going to be a whole lot longer (as it turned out too long for my short attention span). :(

Speaking of transmission gears, my 1962 Vespa 125 had only 3 speeds, as did my 1958 Sears (Puch) 125 motorcycle. And I know someone who owns two 1941 Indian Chief motorcycles and they also have only 3-speeds, along with a hand shift and a foot-operated clutch. Also, the 1970's Honda 750 and 450 Automatics only had two speeds, but their performance was not up to consumer expectations and they did not sell well. All of these motorcycles worked OK. But they all had relatively slow acceleration and their motors could not be tuned to make a lot of horsepower, as the power band would be narrower and then the jump between ratios would have made the vehicles less useful. Increasing the number of gear rations, allowed IC motors to make more power, while providing a smooth transition between gears. Now that 6-speed transmissions have been the accepted norm for the past 30 years (ever since the 1965 Suzuki X-6 came out), most current motorcyclists really believe that if you don't have a 6-speed transmission your are missing something and your motorcycle just isn't really up-to-date. So having a 6-speed transmission could certainly be a worthwhile marketing decision, at least if your are marketing your vehicle to current IC motorcycle owners - and I still believe that is a limited market.

Having said all that, I continue to believe that since electric motors have such a wide range of torque, they really don't need to have as many gears in their drive train as an IC motorcycle. Based upon my limited experience, I feel that they do need at least two speeds, especially as the vehicles become heavier and are asked to carry a passenger. My Zero really struggles when taking off from an uphill stop and lower gearing would certainly help it move to a higher speed where it functions better under load. It still seems to me that a motorcycle powered by an electric motor should work very well with two or three speeds, but I also realize that I am a pretty much uninformed armchair engineering enthusiast and I am just using seat-of-the-pants logic. :confused: So I continue to appreciate this discussion.

podolefsky
04 March 2013, 1220
A couple of things that my limited knowledge doesn't know how well they translate into the current product and discussions - they showed a DC motor graph and talked about voltage limitations for brushes. But, the Empulse uses a brushless PMAC motor. Do those factors affect the basic graphs or performance profiles that they were discussing in that article? Do AC and DC have similar graphs? Is there another voltage limiting (or complicating) factor even if you don't have brushes?

It's true that there are voltage limits due to arcing, but it's not 100V. Brushed motors can go well above that - the Warp 11 HV is 280V, and there are industrial brushed motors that are well above that. But to their point, for the motors they're talking about (Agni and the like), arcing, overheating, and controller limits pretty much keep you under 100V.

The graph in that article is a bit misleading. That graph is what you would get from a permanent magnet motor. AC induction and brushed series / sepex have a different torque curve (it goes roughly as 1/RPM^2).

The parabolic power curve is only if you have no current limit. In reality, controllers have a current limit, so the first 1/2 (or so) of the torque curve is a flat horizontal line, and power climbs linearly (not parabolic). That's true regardless of motor type - it just has to do with the controller current limit.

Electric motors have a power peak that looks a lot like an ICE power peak, sort of like a single or v-twin with a lot of low end. It's the part from 0 to about 1-2k RPM that looks a lot different, where electric motors make torque that is totally absent for ICE.

That part about keeping the front end down vs top speed is pretty right on. Until you get into really powerful motors (read $$$$), you're not going to be doing wheelies and have a top speed of 120 without a transmission. Now, if you don't care about that sort of thing, and you're happy with a top speed of 80-90 and adequate but not blistering acceleration, a moderately powered single speed drive system will do just fine.

mechanic
04 March 2013, 1338
The reason this topic goes on and on is that most of the contributors are doing no work- no research, no basic math and no engineering, they are simply regurgitating the same position (even others opinion or marketing dribble) over and over, only trenching in deeper and deeper.

Marketing spin aside there are a few irrefutable facts about transmission, accept those, do a little work and most of us will come to a similar, more united conclusion.

(sorry for the bluntness- I am not here to make enemies or friends but am interested in DIY motorcycle projects; ICE or elec.)

Fact 1- Transmissions do not increase HP.
Fact 2- Transmissions reduce RWHP (which is why every manufacture claims crankshaft over RWHP... because is BIGGER, how much? approx. 15%)
Fact 3- Transmissions do not increase efficiency
Fact 4- Transmissions add inefficiency (evident of the HP losses)(but may facilitate motor efficiency)
Fact 5- Transmissions do not increase max top speed (top speed is limited by HP, rolling resistance and aerodynamics)
Fact 6- Transmissions reduce top speed (again, they consume HP)
Fact 7- Transmissions can increase rear wheel torque (increased wheel torque will accelerate a vehicle faster)

Want a vehicle to have greater top speed and efficiency use a single speed- period!

However if you want a vehicle to accelerate faster, then multiply the torque. High torque multiplication will result in a lower top speed, want to go faster add/select another gear that has less of a multiplier, and so on.

The question is a classic engineering dilemma (compromise); does the performance of the transmission out weigh the added losses, weight, space and expense, or is there other areas that can be improved (at cost) that can out perform the transmission i.e. motor size and batteries. (again VERY IMPORTANT transmission reduce a vehicles top speed)

If the work results in a vote for a transmission then one needs to be designed for the job (not even close to a $5M task)

If you only know that an electric motor is unique to an ICE than you already know so should its transmission. If you have not already seen/studied a gear ratio plot for an electric motor you have not even done the basic work required to argue your point.

If you cannot find a electric motor gear reduction plot (probably not a google search away) than make your own. Find the torque curve (torque vs. RPM) (a google search away) and multiple each torque curve by a gear ratio (6- speed gear ratios are also available via google) then you will see the redundancy and pointlessness (word?) of a 6-speed box. Take the same spreed sheet and remove gears 1,3 & 5 or 2,5, & 6 and see how that looks. Now you can make an educated decision.

If you cannot do this most basic, elementary work, then you really need to ask yourself why even contribute to the discussion if all you have is uneducated, hearsay.

Once the transmission is finalized than we can start on the............. clutch! LOL

Skeezmour
04 March 2013, 1349
Oh we found at quickly that an electric motor is VERY good at smoking a clutch that was designed for an ICE motorcycle.

podolefsky
04 March 2013, 1428
Fact 1- Transmissions do not increase HP.
Fact 2- Transmissions reduce RWHP (which is why every manufacture claims crankshaft over RWHP... because is BIGGER, how much? approx. 15%)
Fact 3- Transmissions do not increase efficiency
Fact 4- Transmissions reduce (overall) efficiency (where do you think the HP losses go)
Fact 5- Transmissions do not increase max top speed (top speed is limited by HP, rolling resistance and aerodynamics)
Fact 6- Transmissions reduce top speed (again, they consume HP)
Fact 7- Transmissions can increase rear wheel torque (increased wheel torque will accelerate a vehicle faster)


These are all true, but have to be qualified.

-A transmission *can* increase efficiency if it keeps you in an RPM range that has better efficiency gains than the transmission losses.
-If you do 7 (increase wheel torque), then you lose top speed. A transmission lets you get top speed back (minus efficiency losses).

All of this has been hashed out, with data. See the thread with:

This post (http://www.elmoto.net/showthread.php?1924-Transmissions-yeah&p=24191&viewfull=1#post24191)

and

This post (http://www.elmoto.net/showthread.php?1924-Transmissions-yeah&p=24215&viewfull=1#post24215)

You won't find a definitive answer, but you'll get a sense of all the issues involved.

podolefsky
04 March 2013, 1445
I'm not sure if this plot ever made it into a transmission thread, so here it is. Basically shows that to keep up with a Ninja 250, a D&D ES-15 would need a transmission, while an AC-20 wouldn't. Also, the D&D+transmission gets closer to the AC-20 curve, but it needs 5 speeds to do so. You could go with 2 speeds, say 4.6:1 and 2.5:1...then you'd match up at the bottom and top end, but you'd have a big gap in the middle.

Never mind the particulars of D&D and AC-20, just think of them as two different motors and what a transmission can buy you. As an engineering problem, it's always a matter of compromise, and there may be cases where a motor+transmission is a better compromise than bigger motor. Here, the AC-20 is 3x the price of the D&D setup. Scale this up to the Empulse and you *could* be looking at a motor that costs more than the entire bike to get the same performance without a transmission (not sure, just an educated guess).

http://www.colorado.edu/physics/EducationIssues/podolefsky/EV_project/DC_shifting.png

Richard230
04 March 2013, 1705
Speaking of the Empulse's transmission, an owner on the Brammo Owners Forum, just changed his transmission oil for the first time after 250 miles and found this on his magnetic drain plug. :O

Brammo Brian says this is normal and is due to break-in wear of the clutch. :confused:

frodus
04 March 2013, 1722
All of those little particles go into an oil filter in a gas bike. No filter on the Empulse.... So you'll see the magnet pick it up.

Richard230
04 March 2013, 1829
All of those little particles go into an oil filter in a gas bike. No filter on the Empulse.... So you'll see the magnet pick it up.

That is true for an IC motor with an integrated gearbox that had filters (many of the early Japanese motorcycles did not have a filter), but I have also serviced a number of BMW transmissions and two-stoke motorcycle transmissions (everything from my 1963 Yamaha YD3 to my 2003 Aprilia RS50), as well as my 1971 Triumph, all of which had a completely separate gearbox with splash lubrication and I never saw that type of metal swarf when draining the oil. So I don't know what is going on.

jazclrint
05 March 2013, 0016
That is true for an IC motor with an integrated gearbox that had filters (many of the early Japanese motorcycles did not have a filter), but I have also serviced a number of BMW transmissions and two-stoke motorcycle transmissions (everything from my 1963 Yamaha YD3 to my 2003 Aprilia RS50), as well as my 1971 Triumph, all of which had a completely separate gearbox with splash lubrication and I never saw that type of metal swarf when draining the oil. So I don't know what is going on.

Not Brian, but definitely one of the Brammo guys also said that most of those shavings came from the clutch.

flar
05 March 2013, 0050
I still want someone to do a really simple test that I can't do on my transmission-less bike. Take a backpack with 40 pounds in it, and put it on. Accelerate with your transmission through the gears. (This is your "transmission model".) Then lose the backpack (shedding the 40 pounds that the tranny costs you), pick the gear that represents what you'd run if you only had fixed gearing, and do the same run. (This would be your "non-transmission" model.) If you're unsure about which gear would be "best", then try a few.


I'm not sure that would be an accurate experiment for a couple of reasons:

- First, is 40 pounds really a good estimate of a transmission weight? What about the IET? The IET is integrated into the motor housing so they share a common shell, it just doesn't look like a 40 pound hunk of metal (but I obviously haven't weighed it. ;)
- Second, you might want to compare against the same bike but built with a single motor that weighs and costs similarly to the motor+transmission combo. Your experiment might help figure out "what that bike might have been without its transmission but with the same motor", but in the real world, the designer might have bought the next motor up in the product line instead.

I haven't had a chance to do anything exactly like that experiment, but I did do some experimenting tonight. On my way back from the city tonight I did some tests on the highway to pick a gear I could "live with".

1st gear can barely hit 60, not tall enough
2nd gear could hit 70 if I went deep into the warning lights for the tach. Still not tall enough.
3rd gear could hit 70 without warning lights, but got into lights to reach 80. Marginally acceptable, might be acceptable to some on here.
4th gear finally could hit 80 without warning lights. That was acceptable to me.

I then tested 4th gear passing power and it was strong. I could effortlessly zip in front of cars. It felt in the same ballpark as the '13 Zero I rode, but that experience was a month ago.

When I got near my exit I got off on a side road that has a couple of stop signs and a fun twist or two. 4th gear felt positively anemic. It was maybe about as powerful as the '12 Zero I test rode a year ago, but paled in comparison to what I could get out of 1st gear. Yes, it got me around, and I didn't feel it was unsafe and I'm sure many eco-oriented riders would not have any issues with that much power, but once you've felt the 1st gear, there is no comparison. I really don't think 40 pounds would have made a difference, it wasn't even close.

On the rest of the ride home I checked motor temps and they were over 100F in 45F air and stayed that way until I got home. When I finally got to my driveway I checked the charge level and I had used more than 20% more charge(*) to get home then to get to the city - normally the two are very close to each other. (See below for more data about comparing the out and back rides.) I then switched back to 1st to compare power (wheee!) and to ride around the block to see if the motor temps changed. The motor temp dropped 15 degrees in just a minute of riding around the block in 1st (even enjoying myself) - a positive word for cooling.

(* - 20% to get there, 24% to get home)

So, let's look at some of the assumptions in that experiment and I might be able to do something more objective in the future:

- It wasn't exactly the same route out and back since I took a side road on the way back. However, a couple fewer highway miles would tend to favor the efficiency of the return route.
- 10.8 miles out including 8.5 highway miles
- 11.3 miles back including 6.3 highway miles
- I did a couple of highway passing power tests - short, just accelerate for about 2-3 car lengths
- temps were about 50F going to the city and about 45F coming back.
- The dash displayed "cold battery cutback" for the first half mile or so on the return trip, but there is a software update coming that might eliminate that because it turns out the message is displayed on the dash when there is actually no cutback occurring.
- I haven't done any objective experiments to measure the linearity of the battery meter.

teddillard
05 March 2013, 0234
I'm not sure that would be an accurate experiment ...

Fine. No beer for you. :O

Seriously, give it a rest, or start another transmission thread. God knows we need another transmission thread. So does Celine. :p

(edit: OK I went and started it myself: http://www.elmoto.net/showthread.php?2841-Transmission-Thread-Or-Empulse-Thread-You-decide&p=36034#post36034)

Richard230
05 March 2013, 0846
I have to agree with Ted. A specific Empulse transmission thread would probably be appropriate and could provide a location to detail the operation, servicing and reliability of this transmission in the field. And I think that is what most people are really wondering about. How does an electric motorcycle with a transmission actually function when ridden and maintained by Empulse owners? Is it a real advantage that will go in a better direction than a single-speed drive, as happened during the early 1900's when IC motorcycles went from direct drive (with LPA - light pedal assist) to multiple ratios that eventually reached 6 speeds in production motorcycles. Or will the broad torque of electric motors finally make direct drive systems the standard in the industry, as it seems to be in the auto industry? And will anyone try an automatic scooter-type or DCT system in an electric motorcycle? Will cost or marketing win out and in which direction will motorcycle consumers and their dollars go? I think we are all trying to figure out which is best - and no doubt (as usual) time will tell.

Which reminds me: with a transmission, Brammo riders will be able to start (well they actually already have) an "oil" thread and we all know how everyone loves those things. ;)

Natas Damien
05 March 2013, 1231
http://www.cycleworld.com/2013/03/05/electric-motorcycles-eligible-for-sportbike-classes-in-afm-roadracing/

Richard230
06 March 2013, 0952
Here is a link to the entire City Bike article, reproduced by Motorcycle Daily: http://www.motorcycledaily.com/2013/02/md-double-take-2013-brammo-empulse-r/

Shineysideup
18 May 2013, 1921
For an example of how the transmission works in the field, chasing a 750 cc bike:

http://www.youtube.com/watch?v=P-sRfrcpgzY

Ken Will
19 May 2013, 0402
For an example of how the transmission works in the field, chasing a 750 cc bike:

http://www.youtube.com/watch?v=P-sRfrcpgzY

Dude!!
That is the best video I have seen since "The World's Fastest Indian"