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Discussion Starter #1 (Edited)
So, I bought a 31 tooth pulley from a Stryker owner and installed it this weekend when I did the valve lash adjustment. Very glad I did. It still has plenty of torque in the low range and the taller gear has made the top end more enjoyable. Speedometer difference dropped from 5-7mph to 2-3mph. Running 55 in 4th now feels like 65 did in 5th. The difference isn't all that dramatic, but it's a big enough difference to put a big dumb grin on my face. On a side note, I took a corner in the rain a little too hot the other day because the bike sounded and felt like it was going slower. I kept it from going down, but it will take time to get used to the difference in the speed to sensation ratio.
It bolted right up. Belt fit perfectly and there was just enough clearance with the speedo sensor. Would love to go up one more tooth, but that would require a modification to the speedo sensor and possibly a different length belt. Ride safe!


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I plan to do this as my next mod to my 1300 but very rare to get hold of in the uk , buying new maybe the only option
 

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Discussion Starter #3
I got mine here on the forum. It was well worth it. I heard a strange creaking squeak from the belt this morning. I believe it's just adjusted to tight. The last time I set it per the manual it seemed tight and again this time. Will loosen it up some this evening.


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I got mine here on the forum. It was well worth it. I heard a strange creaking squeak from the belt this morning. I believe it's just adjusted to tight. The last time I set it per the manual it seemed tight and again this time. Will loosen it up some this evening.


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loosen it quick before you smoke the transmission countershaft bearing, i hear there a bear to change on a 950
 

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Discussion Starter #5
I brought it straight home and parked it until I can get to it in the morning. I really don't understand it. The manual says to adjust it to 3-5mm on it tightest spot which equals one hash on the belt cover at 10lbs of pressure. I even bought the tension tool. However, every time I adjust it to those tolerances, it ends up being to tight and I wind up re-adjusting it.


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I brought it straight home and parked it until I can get to it in the morning. I really don't understand it. The manual says to adjust it to 3-5mm on it tightest spot which equals one hash on the belt cover at 10lbs of pressure. I even bought the tension tool. However, every time I adjust it to those tolerances, it ends up being to tight and I wind up re-adjusting it.


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a lot 950 tourers had pulleys that are misaligned from the factory more than a few smoked the countershaft bearing because of it, running the belt looser than the factory spec will save the bearing, it's the side thrust from misaligned pulleys the causes bearing failure loosing the belt will unload it some. you may have to change the belt a little sooner but it sure beats splitting cases anyday
 

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Discussion Starter #7
a lot 950 tourers had pulleys that are misaligned from the factory more than a few smoked the countershaft bearing because of it, running the belt looser than the factory spec will save the bearing, it's the side thrust from misaligned pulleys the causes bearing failure loosing the belt will unload it some. you may have to change the belt a little sooner but it sure beats splitting cases anyday

Thanks Pauli466! That's exactly what I was starting to think was going on. Regardless of how well the rear axle is adjusted the belt rides to the outside on the front pulley and rubs the lip. If I adjust the belt to snug it causes it to make noise. I wonder if any adjustment could be made to how the engine is mounted in the frame to adjust the geometry?


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you can remove the front pulley and put a shim behind it to bring it out to get it in line, if the belt was to inside then you would shave some material off on the back side of the pulley to get it in line, other than that you would need to shift the whole engine one way or the other by shaving the mounting bosses on the cases. but for now loosen the belt to be safe
 

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Discussion Starter #9
Ok, I'm a little confused. Putting a whim behind the pulley wouldn't change the angle that it's sitting at so wouldn't the belt just continue to run out? At least for a ways? I have no problem at all putting a 1/16" (or so) shim behind the pulley, but would that be enough?


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your thinking the engine is twisted in the frame? , if that's the case the rear wheel can be adjusted to compensate, doesn't the rear wheel have draw bolts on each side?. a 1/16 shim seems a bit extreme, you only want to go the very minimum to line it up, don't look for perfection, even .5 to 1mm shim would most likely get it close enough to stop the side load on the bearing, and cocking the wheel very slightly, won't affect handling. just remember to try small adjustments, if you go to far it can and will cause problems. if you can lay a straight edge across both pulleys to confirm how much misalignment exists using your eyes on something like that can be very misleading
 

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Discussion Starter #11
The straight edge is a great idea! Yes I was thinking that the two pulleys might not be in line with each other. Never thought that might just not be out quite as far as the other, but that's certainly possible. I'll try shimming it and run it on the lift to see if I can get it in line. I was able to adjust the rear to pull the belt away from the lip of the front pulley, but that ended up causing it to rub in the rear. Sound advice. Thank you!


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Discussion Starter #12
your thinking the engine is twisted in the frame? , if that's the case the rear wheel can be adjusted to compensate, doesn't the rear wheel have draw bolts on each side?. a 1/16 shim seems a bit extreme, you only want to go the very minimum to line it up, don't look for perfection, even .5 to 1mm shim would most likely get it close enough to stop the side load on the bearing, and cocking the wheel very slightly, won't affect handling. just remember to try small adjustments, if you go to far it can and will cause problems. if you can lay a straight edge across both pulleys to confirm how much misalignment exists using your eyes on something like that can be very misleading

Hey Pauli466 I wanted to let you know that I took another crack at the front pulley today. I made some shims out some metal tape I had on hand. Each on was a little less than 1/32" thick. (Guessing). Anyway, it took 2 shims and the rubbing is gone. I put the new larger pulley back on and was able to center the belt on the rear pulley just fine. Took her out for a spin and re-checked it. No rubbing and the belt is still running down the center of the rear pulley. Thanks for the help! Ride safe!!


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Discussion Starter #13
So it's been a few weeks and I thought I'd give an update on this pulley mod. I love it! There was some messing about trying to get it shimmed. I think mine was one of the bikes that the counter shaft was pressed in a little to far. Anyway, it rides great. We rode 2up in the mountains with no noticeable lagging. Still has plenty of torque on the take off. Speedo is closer to accurate and running 65-70 in 5th feels like an easy cruise due to the lower rpms.


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Honesty, I'd have to say no. I have no regrets.
Glad this ended up working out for you. When you originally posted, I was interested of course, and then was disappointed when you started experiencing problems. Having followed the thread, I probably would be hesitant to try it myself but I hope you continue to have good results.
 

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Hey Pauli466 I wanted to let you know that I took another crack at the front pulley today. I made some shims out some metal tape I had on hand. Each on was a little less than 1/32" thick. (Guessing). Anyway, it took 2 shims and the rubbing is gone. I put the new larger pulley back on and was able to center the belt on the rear pulley just fine. Took her out for a spin and re-checked it. No rubbing and the belt is still running down the center of the rear pulley. Thanks for the help! Ride safe!!


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could you post any pictures of these shims you've applied?
 

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I did the swap onto my 1300 but now going to do it to my bolt now , bit more top end speed bit less revs on the freeway/motorway , ive got a cobra exhaust and a KN big air filter kit so it revs free
 

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Well ive done the same swap on my xv950 bolt , its like riding a different bike its miles and miles better , no fitting problems at all well worth hunting a pully out
 

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On all V Star belt driven bikes, the front engine drive pulley is more out than the rear wheel drive pulley, that is why both drive and rear wheel pulleys are much wider than the belt to allow for this variance. This is a rough pic below. It may appear when the wheel is properly aligned that the belt is rubbing up against the outside of the rear pulley. But if the wheel is aligned right, it won't actually be touching.

Many other belt driven bikes don't have wide pulleys like the Star bikes so the belt has no choice but to sit in the middle.
 

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