| Author | Message | |||
     Phelan |
Just thought I'd throw a heads up here. I don't post a lot on the forums anymore, as I'm mostly on Facebook. But I am deep in the development phase of a belt drive conversion for the EBRs. Basically it is a cnc billet, hardened rear pulley of my design, with 70t R gearing, cnc billet left rearset (to mount the idler pulley, 1125 27t front pulley, idler pulley, belt guards, and CR 149t belt. As for the wheel conversion, it is a much more tenuous kit to be a bolt-on affair, and not for everyone, thus extremely limited production. I almost ready for production on this kit. EBR front and rear wheels, rotors, and hardware, cnc billet axle spacers Front and rear, 3 bearing rear axle, cnc billet and Hard coated 65t rear pulley of my design, cnc billet caliper adapter bracket to fit a Brembo P32 or P34 caliper to the unique offset and diameter EBR rear rotor, and Brembo P32 or P34 rear caliper. Pricing is non-conclusive atm, but estimations are about $1300 for the belt conversion and $2500 for the wheel conversion for XBs. (Message edited by phelan on October 09, 2017) | |||
| Froggy |
Does fixing the title get me a discount on that belt conversion? Time to start saving my pennies  | |||
| Phelan |
I'm sure we can figure something out . My goal is actually to offer either the complete kit or just the unique pieces needed for the conversion and let people source the rest themselves if they prefer. The 1125 front sprocket, for example, can be had for as little as $30 on eBay. | |||
| Froggy |
I'd likely buy a complete kit just for the simplicity of it, not that the belt or front sprocket is difficult to obtain. How is the gearing compared to the chain? I'm running a 44T rear on my SX and would love to keep a similar ratio, but I know it isn't something you will get much choice with. Off the top of my head it sounds like the stock 1125R gear ratio. | |||
| Phelan |
Gearing is just a hair shorter than stock 16/41, at 27/70. Without a 71 or 72t pulley for reference, I can't replicate a taller gear. 76t rear would be CR gearing but the wheelbase would be all the way tight in the adjusters if it fit, shortening wheelbase 1.5", and gearing would really be too intense IMO. | |||
| Mnscrounger |
NO firsthand knowledge, but I too have been thinking about this.. V rod belts are the correct pitch and I think the correct width. They come in the longer 150 and 151 tooth configurations. That should allow the shorter gearing without tucking the rear wheel in so far the bike wheelies like a clown car. http://www.1130cc.com/forums/archive/index.php/t-1 01484.html | |||
| Phelan |
Unless the new ones are made by Goodyear, the V-Rod belts are all made by Gates, and reinforced in such a way that they cannot be back bent or the belt will prematurely fail. So a tensioner is out of the question in that scenario, and thus not an option in this application. My kit will utilize a 149t CR belt which is the longest I know of made by Goodyear for HD in this width and pitch. But like I said, the issue isn't actually the belt, it's that I can't make a median pulley more than 70 but less than 76 teeth, because I don't have such a piece for reference to be 3D scanned. | |||
| Phelan |
A 76t rear would be CR gearing and would be brutal on an 1190 on the street. It would be the equivalent of a 45t rear but with 1.5" shorter wheelbase, making it a wheelie monster. | |||
| Hughlysses |
It would be the equivalent of a 45t rear but with 1.5" shorter wheelbase, making it a wheelie monster. You say that like it would be undesirable.  | |||
| Phelan |
Touché | |||
| Mnscrounger |
I was originally thinking " Why do you need to scan the pulley, it can be drawn in CAD. If you have the hub dimensions scanned in, it shouldn't be hard to import that into a new part and construct any pulley tooth number you want around it. If you haven't done this I have some modest CAD skills and would be happy to do it" But in doodling, I see the trouble now. If you're sticking with a 27T front, a 75 tooth rear pulley, with a 14mm pitch belt gives a pitch diameter of around 13.158". That combination gives a final drive ratio of 2.77, close to the popular 2.75 of the 16/44T chain sprocket combo, but a 150 tooth belt would put your two pulley centers at just over 26 7/8" apart, way short of the 32 inches (according to my quick CAD sketch of the chain specs) to get out to near the chains original wheel location. With that belt gearing, to get to the OEM wheel location, you would need around a 170 tooth belt. I think they're out there, but I know nothing of their strength. I haven't done any research into the belt tooth geometry, but most of that data is pretty well known, in fact published on the Gates design website. I'm not trying to bog you down, or pooh pooh your project. I'm just trying to work out for myself, the design details you've already looked at, and hoping I can add new perspective. Let me know if I can help. (I think the project is worth the effort and I may eventually want one too) | |||
| Hughlysses |
The one thing I didn't like about the belt drive on the 1125 was the immense size of the rear sprocket. I imagine this was necessary to get the required ratio while providing a minimum diameter for the front sprocket to avoid bending the belt too severely. I just finished my first chain service on my 1190SX at about 350 miles. That certainly makes you appreciate the maintenance free nature of belt drive, but honestly, it wasn't too big of a PITA. I tightened the chain slightly to ensure no wear on the rubbing block, cleaned, and lubed it. Next time, I'll have the bike on the lift (which will be a big help) and I'll know all the techniques I had to sort out this time. BTW- I used Amsoil chain lube, and it looks close, if not identical, to what was on the chain upon delivery. Goes on thinnish- sets up to a waxy consistency. Edit- NOT the same as the factory lube. Factory chain lube looked sort of grayish when it dried. This stuff is nearly clear with a slight amber tint. Much less visible build-up of lube on the sides of the chain after a thorough lubrication. (Message edited by Hughlysses on October 11, 2017) | |||
| Mnscrounger |
Another wacky idea would be an intermediate drive to keep the pulley size down. I don't know where you would put though. | |||
| Mnscrounger |
Tonight I took a look at the Gates website and did a little research into 170T belts. It turns out one of the Vermeer stump grinders uses a 14mm 170T drive belt( just wider). I think those stump grinders see their share of torque and shock loading so it might be durable enough. The correct part number for a 170T Polychain, carbon reinforced belt is 14MGT 2380-28. 2380 is the pitch times number of teeth, and the 28 is the width in mm. (1 1/8") GT, GT2, and GT3 all are about the belt construction, I found no notation sprocket or belt tooth configuration changed I think a belt in the wider size could be slit into two belts by a bearing house.(at least that's what one of the forums I visited said.) E-bay also had lots of 2380 belts in various widths. Hugh's point about the aesthetics of the ginormous rear pulley is valid, (It doesn't appear it will affect lean angle according to my doodle), but if you want the most desired gearing, AND belt drive, it's a trade off some might accept if the style of the pulley web was close to the wheel style.
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| Phelan |
The Carbon reinforced Gates belts cannot be back bent, which the idler pulley does. This is the reason the 03 XB9 Gates was completely different construction and still not vwry durable, hence the swap to Goodyear belts on the XBs and 1125s, with much more rubber content and corded strength instead of carbon fiber. | |||
| Mnscrounger |
I'm sorry, I forgot that portion of the design. I defer to smarter people whenever possible, but I'd like to raise another thought or two. Thought 1: Goodyear does make 2380 belts in other widths. ( Falcon, Hawk, and Eagle) so a no carbon belt is possible. It just might mean buying enough to make a slitting run affordable. Thought 2: Unlike the XBs, and non race 1125s, where the distance between the pulleys was fixed, the 1190s have a tensioning adjustment available to us. (I understand the distance changes during suspension travel, but the longer swingarm of the 1190 should reduce that effect.) Given that, is an idler even required if the pulley and belt combination is designed well enough to work in that adjustment range? The Goodyear design guide recommends not using idlers, and using center distance adjustments for tensioning. If that's adequate, we might be halfway there already. |
