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Richard230 clicked Likes for this post: The Juiced Drag bike progress post by EVcycle

11 Hours Ago

Richard230 replied to the thread Hawaii to allow motorcycles to shoulder surf.
" And now Toronto is considering allowing filtering for motorcycles at signalized intersections: http://www.motorcycle.com/mini-featu...e-sharing.html "

11 Hours Ago

EVcycle replied to the thread The Juiced Drag bike progress post.
" Finally made it to our second test session of the motorcycle. Made significant gains and we are now
knocking on the door of the 8 Second range in the Eighth Mile. Perfect for a bracket racing bike!
The motorcycle ran flawlessly with turn around times of 20 minutes. Still need gear change or two
( maxed at 4500 rpm) and still only running 67 volts. So I expect even more speed over the next month or two.
Attachment 7771
Starting the burnout. The wheelie bar is not really needed, but it makes a good mount for the GoPro.
Attachment 7770
Finally painted the fender with the body to follow.... we were going to wrap it but the folks here locally
looked a bit "Befuddled" with all the curves on the body...
Attachment 7772
Racing a "Busa" He whipped my ....ummmm well you know. "

13 Hours Ago

Stevo clicked Likes for this post: 1996 Honda Rebel 450 conversion, "rEVel" by Electro Flyers

16 Hours Ago

Stevo replied to the thread 1996 Honda Rebel 450 conversion, "rEVel".
"
Quote Originally Posted by Electro Flyers View Post
Sounds like a fun project. A more useful photo(s) would be from the sides, to better show the components.
Ya! Don't be shy! We like lots of pics! "

16 Hours Ago

Electro Flyers replied to the thread 1996 Honda Rebel 450 conversion, "rEVel".
" Sounds like a fun project. A more useful photo(s) would be from the sides, to better show the components. "

19 Hours Ago

psych0hans replied to the thread Building a track bike on a KTM duke 390 rolling chassis..
" Hi, thank you for your reply. Iím sorry for the confusion, but I have no intention of using any hub mounted setup for the motor. It will be mounted in the same location as the engine with the sprocket in the same place.

The hub motor which was mentioned was for a completely different project, a low cost electric three wheeler for mass production. "

22 Hours Ago

Spoonman clicked Likes for this post: An interview with Zero's new CEO by Richard230

23 Hours Ago

Spoonman replied to the thread Thinking out loud - A hybrid hack.
" Hmmm.. in theory I could see this working with the Hub motor on the sidecar wheel alright; but ideally (and perhaps necessarily) the motor itself would have to be an induction or doubly fed machine rather than PM. Reason being that the PM machines will still generate potentially quite a lot of voltage when freewheeling, and could cog; where as the induction machine can freewheel harmlessly.

The theory follows that you spec this "assist motor" to:
A - motor only, no regen
B - set cut in from standing
C - have a fairly low cut out speed
D - be readily overpowered by the main drive wheel so that low speed maneuvers don't suffer from 'solid rear axle' behaviours.

You'll need to have and RPM sensor on the main wheel and control the assist wheel to match rotation. "

23 Hours Ago

Spoonman clicked Likes for this post: 1996 Honda Rebel 450 conversion, "rEVel" by dmoore

23 Hours Ago

Spoonman replied to the thread Building a track bike on a KTM duke 390 rolling chassis..
" The Agni's are great motors, but I wouldn't even consider using one in a hub config if you're after 100MPH and race spec performance.
Suggest doing some reading up on 'unsprung mass' and its effect on the handling characteristics of a vehicle.

Long story short - *really* bad idea!

If you want that sort of performance, with any respectable measure of handling, you're going to have to keep the motor inboard.
The Agni's will do this, and that frame will fit it (high up in the rear is the usual location), but you'll need a transfer box to the bring the chain inline with the action of the swing arm. "

23 Hours Ago

psych0hans replied to the thread Building a track bike on a KTM duke 390 rolling chassis..
" Figured I'd share my discussion with a very helpful redditor as well.

Quote Originally Posted by psych0hans
Feedback request for Agni 119R. Can it reliably propel a <200kg track motorcycle up to 100mph?

72v Kelly controller will be used with it. The other alternative is a dual motor setup with a 144v kelly controller, but I think 144v will be way overkill for a motorcycle, also it will make the battery pack too bulky and expensive. Mainly expensive.

Quote Originally Posted by jew-iiish
What tire size and gearing are you running? What v and ah batteries were you thinking? Are you fully faired? What’s the exact weight? You’d probably be able to hit it in a quick burst with the 30 kW peak power, but I doubt you could sustain it. 60-75 mph sustained is very doable with these motors.

Quote Originally Posted by psych0hans
Hi, no idea about the gearing, but the tire size will be 110/70 17 front and 140/70 17 rear.

Battery pack should be 96v, not sure about the AH yet. What I do know is, the range only needs to be about 20miles max.

The base is a KTM duke 390 chassis, but it will be fully faired.

No idea about the weight yet.

Thank you for your reply

Quote Originally Posted by jew-iiish
140/70-17 is 77.65 inch circumference. 95-R can do 71 RPM/V. At 96v, you'll get to the max RPM, 6,000 given the correct motor controller and not overly fighting aero/rolling resistance. So at 6,000 rpm, you'd need a 4.4:1 gearing on the motorcycle to hit 100 mph. That's probably going to be a little too low of gearing on the bike for anything but a long straight away, but it might work.

As a bonus: the KTM 390 duke weighs 155 kg. So let's say your bike weighs about the same and you weigh 70 kg, giving you a total weight of 225 kg. This means in order to go 100 kph for 1 hour with a 96 v battery, you would need at least 82 Ah. That's an 8 kWh battery. I also confirmed that you'd need the entirety of the 30 kW from the motor at peak to hit 100 mph, and the number I got was 99 mph. This is with rolling resistance 0.13, aero coef 0.9, and frontal area 0.5m^2.

Note: You'll need a higher voltage controller than 72v to hit those numbers, since this requires max RPM. 72v is 5,100 rpm, so you'd need to run 3.75:1 gearing for the same numbers, which is even harder on the motor. You'll need 110 Ah for the hour at 100 kph.

Edit: You'll get about 128 kph continuous with this motor (16 KW continuous) at the numbers I guessed.

Quote Originally Posted by psych0hans
WOW! Thank you so much for your reply. I spoke to the Agni guys and they recommend going with a dual 119R setup in series. The single 119R can handle up to 90v, so he said the biggest battery I should think of getting is an 84v setup, which at peak voltage will probably top out just above 90v.

Since this is a hobby build, everything will depend on how much money I can get out for this. The reason I’m not too keen on a 144v setup is because of the size/weight and more importantly the cost to get the needed AH.
"

1 Day Ago

T Rush replied to the thread Hawaii to allow motorcycles to shoulder surf.
" whelp....if there is so much traffic in Hawaii that I have to think about lane splitting or riding up on the shoulder...I'm kinda glad that I haven't ridden there or Alaska
(yet...and PortoRicco? isn't going thru Chicago and Atlanta bad enough, forget about Boston as thats the one place that they said i couldn't ride from 'thar to near'[and they where right, but I found some ally ways and parkinglots to cut thru to make it] I can do Cal, NYC and even DC) "

1 Day Ago

dmoore replied to the thread 1996 Honda Rebel 450 conversion, "rEVel".
" I found the problem. Nothing wrong with the controller. Faulty contact at the inline fuse holder supplying the controller logic power. Quick fix. Back to 100% "

1 Day Ago

Stevo replied to the thread Hawaii to allow motorcycles to shoulder surf.
" DUH! I bet "shoulder surfing" is far safer than lane splitting. But you know a**holes in cars will use the shoulders too! "

1 Day Ago

Stevo replied to the thread Dice has Plans: 10 days and counting!.
" Big Bummer "

1 Day Ago

Stevo replied to the thread Building a track bike on a KTM duke 390 rolling chassis..
" Good luck with the sponsorships! I did the same thing when I first started this hobby. I contacted several companies and one named Positec, who manufactures and imports the WORX line of electric lawn mowers and weed eaters here in USA, came through!! They sent me free of charge several batteries and chargers and odd and ends switches. It was generous of them and not too cheap to ship. The batteries didn't suffice in the end, but I still keep their logo on my bike to thank them for their kindness and support! This was way back around 2010. Thunderstruck EV in Sebastopol, CA have been very helpful also, so I support them with logos on my bike as well. Another company called CK Worldwide, who manufactures and sells Welding equipment, helped me out quite a bit and provided me with some free TIG equipment. Sometimes you will be truly amazed by what happens when you reach out for help. "

1 Day Ago