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DaveAK
11 May 2011, 1046
If anyone is considering a belt drive system may I recommend looking for a Buell Blast rear sprocket/pulley/(?). I took my test on one of these awful bikes and while I hated the bike I couldn't help but notice the large diameter of the rear sprocket/pulley/whatever it's supposed to be called thingamajig.

Of course, you'll need to find an appropriate size front whatzit, but I think there may be more available options there. I haven't researched the specs for the Buell rear watyamacallit, but it should be real easy to mount to just about any bike.

DaveAK
11 May 2011, 1053
OK, these guys are calling it a sprocket, so we'll go with that. And it's 80T!

http://cgi.ebay.com/ebaymotors/Buell-Blast-80t-Rear-Sprocket-Cover-NEW-P3-2001-_W0QQcmdZViewItemQQhashZitem588df2b271QQitemZ38033 8614897QQptZMotorcyclesQ5fPartsQ5fAccessories

ZoomSmith
11 May 2011, 1156
My v2.0 is hopefully going to be belt drive. The problem with the Harley belts is the tooth pitch doesn't allow for the smaller front sprocket we typically need for our gearing (4:1 to 5+:1).

I've gone through the Gates design guide many times and the only way to make reasonable gearing work is to use a smaller pitch belt, which means custom pulleys and big $$.

DaveAK
11 May 2011, 1207
I know these kinds of things are a problem with belt drive, so that's why I posted about the Buell rear sprocket. I was hoping its large diameter would make it easier to get the ratio we need. Do you know if it uses the same pitch as any other particular models? I wouldn't imagine the Buell is unique, but I don't know what options there are for front pulleys across the Harley range. One thing I did note was that the rear pulley was about two inches wide, while the belt was about an inch and lined up against one edge.

The other thing that I thought might be a solution was a custom front pulley. Should be less costly than custom manufacturing the rear. Alternatively you could add in a jackshaft, but you could do that with any design so kinda defeats the object somewhat.

DRZ400
11 May 2011, 1215
Lots of Suzuki Savage belts, pulleys, wheels on ebay. That bike has been unchanged for pver 15 years.

ZoomSmith
11 May 2011, 1218
Looks like the Buell uses a 11mm pitch belt, not the 14mm like the H-D & Savage.

We would need a 20 tooth front pulley......

Dangit Dave, I'm supposed to be working!!!

BTW: check out this guy's attempt to convert a VFR to belt drive.
http://www.vfrdiscussion.com/forum/index.php/topic/39497-unchain-my-bike-or-so-i-thought/

ZoomSmith
11 May 2011, 1228
Crud. No 11mm data for Gates PolyChain.

So we are stuck with whatever belts & pulleys the OEM's have available (or to machine our own).

Oh well, back to designing an 8mm belt drive system....

DaveAK
11 May 2011, 1234
So all we need is a machine shop ....

Allen_okc
11 May 2011, 1235
man i'll sure be glad when manufacturers recognize the need for parts like this...

podolefsky
11 May 2011, 1353
Zero uses a belt drive on some of their new models. They're geared 28:98 I think, so pretty high. I asked them and they directed me to Gates.

I don't think you can go much smaller than 30T with 14mm because the belt can only bend so much, especially at high RPM.

There are 8 mm pitch pulleys that will work, 112:24 for example (about 5:1). These can be found on e-bay pretty cheap...except they're cast iron and like 20-30 lb. You could machine away most of the bulk and bolt on an aluminum hub to save weight. But...gears this big don't usually have flanges. :(

I looked into this a lot and I think if you want belt drive at the ratios we use, you'll need a very high ratio or two reductions.

Machining gears like this is serious business - not something that can be done simply (or cheaply) in any old machine shop.

Brutus
11 May 2011, 1359
I can save you all a bunch of homework here because I desperately wanted belt drive for my primary drive. You are only going to find 2 companies that MIGHT be willing to make you custom pulleys for belt drives for a primary or for final drive. BDS industries in Walnut Ca. and Karata belt drives in Pa. Don't expect a price anyone can afford though, I was quoted 25k to build my prototypes. Also that 80t sprocket is pretty useless to get a bike to get rpm and/or top end speed . And belts are a whole other animal all together, by that I mean sizes are limited and having one "custom" made is pretty much out of the question.

podolefsky
11 May 2011, 1403
One more issue, unless you have a bike set up for belt drive, you will likely need to take off the swingarm to put on the belt. Not exactly ideal.

Besides, chains sound cool, IMO.

DaveAK
11 May 2011, 1410
Zero uses a belt drive on some of their new models. They're geared 28:98 I think, so pretty high. I asked them and they directed me to Gates.

I don't think you can go much smaller than 30T with 14mm because the belt can only bend so much, especially at high RPM.

There are 8 mm pitch pulleys that will work, 112:24 for example (about 5:1). These can be found on e-bay pretty cheap...except they're cast iron and like 20-30 lb. You could machine away most of the bulk and bolt on an aluminum hub to save weight. But...gears this big don't usually have flanges. :(

I looked into this a lot and I think if you want belt drive at the ratios we use, you'll need a very high ratio or two reductions.

Machining gears like this is serious business - not something that can be done simply (or cheaply) in any old machine shop.


I can save you all a bunch of homework here because I desperately wanted belt drive for my primary drive. You are only going to find 2 companies that MIGHT be willing to make you custom pulleys for belt drives for a primary or for final drive. BDS industries in Walnut Ca. and Karata belt drives in Pa. Don't expect a price anyone can afford though, I was quoted 25k to build my prototypes. Also that 80t sprocket is pretty useless to get a bike to get rpm and/or top end speed . And belts are a whole other animal all together, by that I mean sizes are limited and having one "custom" made is pretty much out of the question.
Sounds like a challenge to me. I accept.

teddillard
11 May 2011, 1429
...how the hell did I miss this opportunity to say NO PROPER MOTORCYCLE runs a BELT.

HAHAHahaahaa

(ducks, runs away...)

DaveAK
11 May 2011, 1430
Good thing it's not for a proper motorcycle, just an electric one. :p

teddillard
11 May 2011, 1442
Good thing it's not for a proper motorcycle, just an electric one. :p

...not for any kind of motorcycle, in truth.

But anyway, Dave, this thread started kind of strange... "if anybody's considering", like that. Are you considering? Is this for your current build? (...is an intervention necessary?) Or just bored at work?

DaveAK
11 May 2011, 1459
...not for any kind of motorcycle, in truth.

But anyway, Dave, this thread started kind of strange... "if anybody's considering", like that. Are you considering? Is this for your current build? (...is an intervention necessary?) Or just bored at work?
Not sure why you're against belts, but one thing I've learned on this site is everybody is against something that someone else has an interest in. (Transmissions maybe? :)) C'est la vie.

Anyway, I'm not particularly interested, but I was pretty sure the topic has come up before. I recall the biggest problem being getting the ratios suitable for an electric bike. I couldn't help but notice that the Buell Blast I was taking my test on had a really large rear pulley that I thought would be a suitable starting point for a belt drive. It's probably a similar diameter to my rear sprocket.

And I'm always bored at work. :(

Oh, and since Noah and Chris have thrown down the gauntlet, I'm much more interseted now. Add to that your low regard for belt drive and how could I possibly turn down an opportunity to do some tinkering with this stuff? :D

Richard230
11 May 2011, 1508
I like belt drives. I had one on my 1985 Kawasaki EX305-B1. The belt was made by the Japanese company "Bando" (naturally). Belts are light, efficient, rarely need adjusting, last a long time and need virtually no maintenance. However they do require the disassembly of the swing arm to replace, can be damaged when riding off road due to a rock getting wedged between the belt and the cogwheel, they are typically a little more expensive than a premium chain, can be tough to find except from an OEM dealer and the cogwheels very difficult to find and adapt to a motorcycle that originally had a chain drive. Also keep in mind that belts come in exact lengths and your motorcycle has to have exactly the right distance (to a fraction of an inch) between the front and rear cogwheels (or if you prefer, sprockets).

If anyone manages to fit a belt drive to a motorcycle that was not intended for one, it should be an interesting story. I think the belts may be available to the public, but I am not sure about being able to locate a front and rear cog wheel of exactly the right width, pitch and diameter, and that would have a universal fit on a chain-driven motorcycle. Maybe a belt drive could be sourced from an aftermarket Harley accessory company.

One other comment: BMW installed a belt drive system on their ST800S (now discontinued) and ST motorcycles. However, all of their new models based upon that motor, including the F800/650GS and F800R are now using chain drive. I have no idea why, but BMW seems to be getting away from the belt drive system and sticking with chain drive, or their old stand-by, shaft drive. My guess is that they have done so due to cost - which seems to be one of their major considerations lately.

ZoomSmith
11 May 2011, 1513
I talked with Phil Ross at Supermax, and he only does 14mm belt components.

There are actually lots of places that machine the pulleys for standard Gates profiles, but it definitely requires a specialty shop. We used Motion Systems for synchronous drive stuff at work. But I'm inclined to do it with off the shelf pulleys first and modify as needed.

The chain sound is only mildly annoying to me, but fling cleanup, lubing, and adjusting are just more stuff I'd prefer not to be doing.

(Richard: I had a Kawasaki GPz 305 with belt drive, and loved it)

podolefsky
11 May 2011, 1523
You can get blanks like this on e-bay (http://cgi.ebay.com/ebaymotors/REAR-BELT-PULLEY-SPROCKET-HARLEY-BLANK-70T-1-1-2-IRONHO-_W0QQcmdZViewItemQQhashZitem3cb61f0fb0QQitemZ26075 3526704QQptZMotorcyclesQ5fPartsQ5fAccessories), then machine to match your bike. But I've only seen them as large at 70T, and I'm not sure what the pitch is (probably 14mm).

DaveAK
11 May 2011, 1539
You can get blanks like this on e-bay (http://cgi.ebay.com/ebaymotors/REAR-BELT-PULLEY-SPROCKET-HARLEY-BLANK-70T-1-1-2-IRONHO-_W0QQcmdZViewItemQQhashZitem3cb61f0fb0QQitemZ26075 3526704QQptZMotorcyclesQ5fPartsQ5fAccessories), then machine to match your bike. But I've only seen them as large at 70T, and I'm not sure what the pitch is (probably 14mm).
The Buell Blast rear was definitely larger diameter than any of the Harleys in the shop and it seems as though the Harleys are 14mm pitch while the Buell blast is 11mm. I've found a couple of Goodyear belts on eBay for the Buell for just $200 a piece! I think the big issue would be whether I could go as small as 18T on the front, (assuming the Buell rear is 80T). That would be more likely achievable with the smaller pitch and would get me close to my current ratio. Then of course there's the issue of the belt length.

Still, if I was doing this as a general thing I wouldn't go down this route. If I can make it work for my bike specifically then I might convert it this winter as an intersting project. All I need now is the "gear" profiles for various belt options. Do the manufacturer's supply these in a readily available fashion?

Richard230
11 May 2011, 1545
ZoomSmith, I really loved my GPZ305, too. It ran and handled great. Unfortunately, Kawasaki made the unfortunate decision to locate the CD ignitor box right on top of the cylinder head and my bike would eat them every 8000 miles, when a thermistor inside the block of plastic would die. After replacing a couple of these boxes at around $250 a pop, I traded the bike in on a new pearl white 1986 VFR700FII. When my daughter graduated from UCSD, I gave her that bike and it now has 85K miles on it. Other than going through a bunch of voltage regulators and batteries and a bit of an electrical fire under the left side cover, the VFR bike has been bulletproof.

podolefsky
11 May 2011, 1553
Try this : Powergrip HTD (http://endless-sphere.com/forums/download/file.php?id=55873)

DaveAK
11 May 2011, 1608
Try this : Powergrip HTD (http://endless-sphere.com/forums/download/file.php?id=55873)
Thanks!!

An 8mm pitch is available with an 18T standard sprocket, but they don't list an 11mm. The 14mm starts at 28T. Looks like 8mm would be the most likely to work.

podolefsky
11 May 2011, 1652
I've seen 8mm pulleys as large as 72-80 tooth. Actually, blower pulleys can be found in 8mm and like 68T. Not sure if they are HTD, and you need to turn them down and add flanges. But at least they're aluminum.

teddillard
11 May 2011, 1715
... Add to that your low regard for belt drive and how could I possibly turn down an opportunity to do some tinkering with this stuff? :D...

...played like a fish, sir, played like a fish. :)

DaveAK
11 May 2011, 1718
...played like a fish, sir, played like a fish. :)
I'd still like to know what your reservations are so I could at least attempt to address them.

podolefsky
11 May 2011, 1721
I'd still like to know what your reservations are so I could at least attempt to address them.

Belt drives are for pansy-a$$ Harley riders.

teddillard
11 May 2011, 1828
Well, then... seriously? Belt drives, to me, are solutions for problems that never existed. Chains are an elegant, efficient, workable design, there was never any need for anything else.

Yes. It's an idealogical argument, and is rooted in my stone-axe sense of what a motorcycle is all about.

So there. :p

From a practical standpoint, one of the things I like to do, even on an ICE bike, is to mess with gear ratios. When you do that, you need to adjust the length of the chain. Or the belt. Good luck with that... :) If you don't hit your ratio right, you need a new belt, and you have to hope they make one the right length.

As far as the usual arguments for belts, I don't care that they're quieter, I honestly enjoy the ritual I've performed for over 40 years of oiling and adjusting the chain... half the reason I love motorcycles is working on them.

jpanichella
11 May 2011, 1844
Well, then... seriously? Belt drives, to me, are solutions for problems that never existed. Chains are an elegant, efficient, workable design, there was never any need for anything else.

Yes. It's an idealogical argument, and is rooted in my stone-axe sense of what a motorcycle is all about.

So there. :p

I can see the appeal of an entirely greaseless bike (unless you decide to throw a transmission in there :) ), and belt drives are remarkably quiet. But I'm of the philosophy that if it ain't broke, don't spend a bunch of money to fix it.

Harold in CR
11 May 2011, 1910
OK. No laughing.

Over on the ES, there are a couple guys that made their own "Timing type" Pulleys. They took "V" pulleys, and turned some of the "V" sides down, so the sides were fairly straight on the inside. Then, used a special Epoxy, and had a belt cut to length to exactly match up at the joint, and put the epoxy inside the pulley, and wrapped and secured the ends of the belt. After the Epoxy set, they peeled out the belt and did minimal cleanup on the epoxy.

This was for the rear pulley on high powered EBikes and Reverse Trikes.

I thought about drilling into the base of the "V", after it was turned, and inserting pins, like screws or very short roll pins, to add more strength to the epoxy, so the epoxy itself would not take all the torque.

I see no reason why this will not work.

Also, there is a thread about the Trike guy, that found a supply of special belt, and he has had no problems with that drive system.

Yes, it's not a MOTO, but, I can't see it not working. Also, it's entirely possible to make the rear pulley out of a composite material, and simply put "Rims" on each side, and do the Epoxy thing. Just about all this work could be done without major tools.

DaveAK
11 May 2011, 1938
Well, then... seriously? Belt drives, to me, are solutions for problems that never existed. Chains are an elegant, efficient, workable design, there was never any need for anything else.

Yes. It's an idealogical argument, and is rooted in my stone-axe sense of what a motorcycle is all about.

So there. :p

From a practical standpoint, one of the things I like to do, even on an ICE bike, is to mess with gear ratios. When you do that, you need to adjust the length of the chain. Or the belt. Good luck with that... :) If you don't hit your ratio right, you need a new belt, and you have to hope they make one the right length.

As far as the usual arguments for belts, I don't care that they're quieter, I honestly enjoy the ritual I've performed for over 40 years of oiling and adjusting the chain... half the reason I love motorcycles is working on them.
OK, so no good reason. Got it. ;)

mpipes
11 May 2011, 2036
mcmaster.com has all kinds of synchronous pulleys and belts but in order to get a 5:1 ratio means using a 1/2" wide belt with 3/8" pitch, and I don't know if that would handle the load and RPM. Less than $20 for a 12 tooth pulley and I think it was $80 for a 60 tooth, then belt around $100, someone might not mind doing some testing. The pulleys are available with standard shaft sizes and keyways.

podolefsky
11 May 2011, 2110
Starting on p. 30 of the HTD bible (http://endless-sphere.com/forums/download/file.php?id=55873) are power ratings for various belts. HTD are "high torque drive", very strong belts.

For an 8mm belt, 20 tooth pulley, at 4000 RPM, you get 7.07 kW / 25 mm of belt width. If I'm reading the chart correctly, that means you would need a 75 mm wide belt to handle a 21 kW (28 HP) system.

For a 14mm belt, 28 tooth pulley, 4000 RPM, 20.18 kW / 25 mm.

I think Harley belts are 1 1/8" - 1 1/2". I won't say definitively since I'm not sure, but I'll bet 1/2" isn't going to cut it.

ZoomSmith
11 May 2011, 2346
I think you are better off with the Gates PolyChain GT Carbon. If you look at H-D and BMW drives, the tooth profile is the PolyChain type.

I'm thinking 27 & 112 tooth pulleys. See pg. 50 of the Design Guide for a 21mm wide 8mm pitch belt on 27 tooth sprocket: 47hp

Also keep in mind the Design HP is the Duty Rating x Service factor.

http://gates.com/catalogs/file_display.cfm?file=PC_Carbon_Drive_Design_Manua l.pdf&thisPath=gates\catalogs

EVcycle
12 May 2011, 0309
Belt drives are for pansy-a$$ Harley riders.

Yes they are, thank you very much..... :)

IMHO, This stuff is just really heavy compared to aluminum chain sprockets.
I still think I have one off the the EN500. The front belt "sprockets" are normally steel.
Blower units are available, but you can not get too small as the belts do not like that small of a bend.

Still, an interesting project.

I do not hear the chain so much as wind noise.... caus I try to go fast.... :)

teddillard
12 May 2011, 0311
OK, so no good reason. Got it. ;)

Wait, I like belt drives. They keep you distracted from transmissions. :O
http://s.costumzee.com/users/nicole19-3135-full.gif

sparky_mark
12 May 2011, 0341
Why not just bolt an electric motor to a Buell? Keep the gearbox. Use the belt drive. Problem solved :)

podolefsky
12 May 2011, 1340
I think you are better off with the Gates PolyChain GT Carbon. If you look at H-D and BMW drives, the tooth profile is the PolyChain type.

I'm thinking 27 & 112 tooth pulleys. See pg. 50 of the Design Guide for a 21mm wide 8mm pitch belt on 27 tooth sprocket: 47hp

Also keep in mind the Design HP is the Duty Rating x Service factor.

http://gates.com/catalogs/file_display.cfm?file=PC_Carbon_Drive_Design_Manua l.pdf&thisPath=gates\catalogs

Thanks. Does HD use the Polychain GT, GT HTD, or GT2? According to this chart (http://www.pfeiferindustries.com/pdfs/Tooth%20Profile%20and%20Pitch%20(Interchangeabilit y).pdf), they're not interchangeable (but they're all Polychain).

ZoomSmith
12 May 2011, 1349
GT Carbon replaced the GT2 which replaced the GT.
H-D will never tell you which series it is, but Phil Ross at Supermax indicated that GT Carbon is what they are using now. http://www.supermax.net/