Clutch offset STM's and stock

[DMCTurbo]

Yes, if you mean 61.1mm, that's what it was from the factory.

Yes sorry 61.1mm.

 

[Motorhead]

That sucks for us

I totally agree. I did not blow a belt until about 1100 miles last year, but I broke it in by the book, so first 500 miles were really easy. Did not blow the belt until I really rode it hard, but I was still disappointed whereas I had been hearing about a lot of winders doing that, and my past experiences with Yamaha clutches were not about any of that.

How about your dealer giving it a go on warranty. Mine did!

 

[DMCTurbo]

My dealer told me when I picked it up that they spent a lot of time on clutch alignment. I'm glad they did because I haven't had any issues. Now another thing to note is I never ran the sled with the stock clutching. I had an Ulmer kit in the primary from day 1.

 

[Soupy]

I totally agree. I did not blow a belt until about 1100 miles last year, but I broke it in by the book, so first 500 miles were really easy. Did not blow the belt until I really rode it hard, but I was still disappointed whereas I had been hearing about a lot of winders doing that, and my past experiences with Yamaha clutches were not about any of that.

How about your dealer giving it a go on warranty. Mine did!

Yes they're up for looking at it for warranty but made it clear that if there are parts that are worn, that's a different issue, I'm in pretty good w my dealer. What did your dealer find was the problem?

 

[Motorhead]

Yes they're up for looking at it for warranty but made it clear that if there are parts that are worn, that's a different issue, I'm in pretty good w my dealer. What did your dealer find was the problem?

He was very good with all. He had said that they would check all with clutches and also see why I was not getting good fuel mileage. He has a few race sleds (Winders) and they set the offsets on those at the 61 end of the spec, so he was to check my clutches and leave the offset as suggested. Also replaced my fuel regulator (whole rail) from new one sitting on show room floor. Only put 300 miles on last year after they worked on it. Mileage increased to 15 mpg as he said it should be, if ridden normal, and the jurors are still out on belts, whereas 300 is not enough to say but the belt still looks new.

This year he put a TD 245 tune with his stock muffler mod and clutch kit. His kit includes machining primary sheaves and machining secondary spring pocket (coil bind). So we shall see!!

 

[SuperTurbo]

I don't see the difference between video 1 and 4? Is the belt bending......hence you removed some material to push it closer to the frame?

Maybe this helps?

Fixed
Wrong offset

 

[Fleecer]

Maybe this helps?
View attachment 134820 View attachment 134821 Fixed
Wrong offset

Superturbo, that helps trememdously, as now I see what you are referring to.....sorry to be a retard, but I have a belt eater and would like to find a cure.

Let' discuss the fix: It appears as though adding shims behind the secondary to push it out or away from the frame would better line up the clutches. However from reading your post, you removed material and essentially pushed the secondary clutch in or closer to the frame. Can you clarify this?

Lastly, what if a guy machined 5mm off the inner hub of the secondary and re-installed without any shims. Or added shims under secondary clutch bolt if secondary needed to go out. Would the clutch float and take it's place on its own?? Thanks.

 

[Soupy]

Superturbo, that helps trememdously, as now I see what you are referring to.....sorry to be a retard, but I have a belt eater and would like to find a cure.

Let' discuss the fix: It appears as though adding shims behind the secondary to push it out or away from the frame would better line up the clutches. However from reading your post, you removed material and essentially pushed the secondary clutch in or closer to the frame. Can you clarify this?

Lastly, what if a guy machined 5mm off the inner hub of the secondary and re-installed without any shims. Or added shims under secondary clutch bolt if secondary needed to go out. Would the clutch float and take it's place on its own?? Thanks.

Opppsite, secondary needs to move further inward than simply removing shims would allow, which is why he removed material from the secondary shaft.

 

[**sj**]

Or the primary is too far inward for whatever reason (machining or taper issue)..

....this is why I said reinstall the oem primary as per spec's and lets see the same demo...assuming the results were the same...

lets examine possible solutions...

If all shims are removed and the clutch is sitting against the bearing...could the bearings inner race ( $20 bearing) be out of spec where another bearing gains you .100 or could the bearing pocket be machined off or have something in it that is pushing the bearing slightly out?

since the motor mounts are not adjustable... and if both clutches net the same....I would look into the crank stub shaft assembly ...again...bearings and splines to splines ....

 

[Fleecer]

Or the primary is too far inward for whatever reason (machining or taper issue)..

....this is why I said reinstall the oem primary as per spec's and lets see the same demo...assuming the results were the same...

lets examine possible solutions...

If all shims are removed and the clutch is sitting against the bearing...could the bearings inner race ( $20 bearing) be out of spec where another bearing gains you .100 or could the bearing pocket be machined off or have something in it that is pushing the bearing slightly out?

since the motor mounts are not adjustable... and if both clutches net the same....I would look into the crank stub shaft assembly ...again...bearings and splines to splines ....

Definitely some possibilities SJ. I too will be removing my belt guard and looking into this after the holidays. At least Superturbo has lead us into possibly developing a path forward in curing these belt shredders.

 

[theewarrior]

There's a lot of guys that haven't blown a belt like myself. 3500kms, 1500 of them with power trail

So did you ever measure your offset?

 

[theewarrior]

Maybe this helps?
View attachment 134820 View attachment 134821 Fixed
Wrong offset

Did you check your offset measurement before and after you fixed it

 

[ClutchMaster]

Deleted by me

 

[theewarrior]

Maybe someone that is having good luck with belts could do a a full alignment on all 3 measurements for us

 

[ROCKERDAN]

Did my 1200 by eye, have a similar video on my youtube page last year. On the doo I had to shim to get NO DOGLEG thru the shift.

My belt temps came down quite abit after that.

I agree anyone running hot belt, or blowing belt needs to bite bullet, worst part is the rivets. But then you can see it and set it up to run straight thru the shift. As mentioned 61mm may or may not work for all as each sled has slight variations and belt variations.

Dan