Clutch offset question

[ROCKERDAN]

New batch of belts are in , no updated number ....

Are you saying Yamaha has a new belt out for us? That would be interesting.

 

[ROCKERDAN]

Good advice Dan. This is how I did it in case it helps anyone. I had 2 yamaha shims (1mm and 2mm) designed to slide on the jackshaft behind the secondary. I used these to measure what was missing. I installed the alignment tool in secondary, lowered it against gonogo gauge in the primary like in rockerdans pic and slide 2mm shim between bar and gonogo gauge for perfect fit. Hence clutch had to go in 2mm for perfect spec. Since I had no shims behind secondary from the factory I had 3mm machined, then put 1mm shim behind secondary. Also had 2mm machined off plug on clutch bolt. The 2mm shim will sit in the toolbox forever now with no use. Lol. Hopefully this extends belt life.

I hear ya....

For what its worth, Cannon reminded me(man i must be getting old?) about Daves stub shaft. While I was all over reading about Daves stub shaft(harmonic balancer), I was after other aspects of the stub shaft, but forgot that one little tidbit of IMPORTANT info Dave mentioned, saying that his stub shaft is a tad longer then stock, so it moves the primary clutch outward(1/8" or 3.175 mm) which is basically the same amount we all are machining off secondaries.

So Dave has been all over this whole alignment issue from day one.

Dan

 

[Doowithblue]

Easy enough fix i guess. Just add a few more shims behind secondary i suppose.

 

[Shagnos]

Correct me if I am wrong. We have a belt adjuster with “float”. Just machine the hub on the back of the secondary, throw a 1mm shim against the clip. The secondary will “float” to the correct offset. Done.

 

[1nc 2000]

Correct me if I am wrong. We have a belt adjuster with “float”. Just machine the hub on the back of the secondary, throw a 1mm shim against the clip. The secondary will “float” to the correct offset. Done.

All depends on how much "float" you have.

 

[Mototown]

You can verify your max float by taking out the secondary spring , put back on sled with the secondary fully closed & fully open . ( make sure your rollers are touching ramps ) . Then shim it . U should set your belt height before u do this .

 

[Mototown]

Are you saying Yamaha has a new belt out for us? That would be interesting.

No the stock 8jp belts were on back order ,the new shipment just came in . I was hoping Yamaha was coming out with a 8jp-01

 

[Shagnos]

You can verify your max float by taking out the secondary spring , put back on sled with the secondary fully closed & fully open . ( make sure your rollers are touching ramps ) . Then shim it . U should set your belt height before u do this .

What is the difference, 1 mm or 4mm of “float”. Won’t the secondary just “float” to the correct offset? Path of least resistance?

 

[KnappAttack]

I'm taking the float out of my Winder completely. IMO the secondary is getting stuck in the outboard position under power and popping the belt along with improper offset. I've ALWAYS eliminated the float out of the Apex's, old Cats and Doos just because there is no way IMO a driven can float to proper position when under power and pouring the power to it. Have never had problems blowing belts with a non floating secondary even on big power turbo Doo's and Apex's.

Going back to old Cat reverse cam driven shims in between the driven sheaves to set the belt height and bolt the driven down right against the clip and bearing after setting with the Hurricane Bar. It appears like I still need to machine 2+MM off my driven even after taking all the shims out to get things lined up for 1:1.

Yamaha/Cat really blew it on the alignment and testing here!

 

[Mototown]

If u have a float set up , 1 to 1.5 mm is better. The secondary moves around from on & off throttle Set your offset between 58-59 mm . Make sure your clutch surfaces are clean with lacquer thinner before u put a new belt on . ( if you go to zero float, just watch because you can side load your jack shaft bearings)

 

[Shagnos]

I'm taking the float out of my Winder completely. IMO the secondary is getting stuck in the outboard position under power and popping the belt along with improper offset. I've ALWAYS eliminated the float out of the Apex's, old Cats and Doos just because there is no way IMO a driven can float to proper position when under power and pouring the power to it. Have never had problems blowing belts with a non floating secondary even on big power turbo Doo's and Apex's.

Going back to old Cat reverse cam driven shims in between the driven sheaves to set the belt height and bolt the driven down right against the clip and bearing after setting with the Hurricane Bar. It appears like I still need to machine 2+MM off my driven even after taking all the shims out to get things lined up for 1:1.

Yamaha/Cat really blew it on the alignment and testing here!

So basically the only time it’s properly lined up is when the clutches are operating at 1:1? What about the rest of the time?

 

[KnappAttack]

So basically the only time it’s properly lined up is when the clutches are operating at 1:1? What about the rest of the time?

Angles are different on drive and driven, so at lower ratios the driven wants to come out about 1 mm or so if floating. Has never been an issue for me in the past to lock them down. For the most part, you run more % of time in that 1:1 ratio. Put a camera in there and you'll see what happens.

With big power being thrown down and floating, IMO the driven gets stuck in the outboard position, and thats the reason I have always bolted the driven into position against the bearing. I used to use a large o-ring to keep constant pressure on the driven and not overload the jackshaft bearing trying to pull the jackshaft thru the driven. Doing this it would hold the driven against the bearing at all times. Never had an issue with belt wear let alone blown belts doing it this way on any of my big power turbo sleds.

Not saying that float wont work, but it sure has been an issue for me floating on this sled so for, so now I'm going the other way and locking it down. I know one thing, it can't get any worse than I've had so far with it floating. I'll know when the snow flies how it pans out.

 

[ROCKERDAN]

Agree Mike...

 

[cannondale27]

Angles are different on drive and driven, so at lower ratios the driven wants to come out about 1 mm or so if floating. Has never been an issue for me in the past to lock them down. For the most part, you run more % of time in that 1:1 ratio. Put a camera in there and you'll see what happens.

With big power being thrown down and floating, IMO the driven gets stuck in the outboard position, and thats the reason I have always bolted the driven into position against the bearing. I used to use a large o-ring to keep constant pressure on the driven and not overload the jackshaft bearing trying to pull the jackshaft thru the driven. Doing this it would hold the driven against the bearing at all times. Never had an issue with belt wear let alone blown belts doing it this way on any of my big power turbo sleds.

Not saying that float wont work, but it sure has been an issue for me floating on this sled so for, so now I'm going the other way and locking it down. I know one thing, it can't get any worse than I've had so far with it floating. I'll know when the snow flies how it pans out.

Still would like to see someone do the math the factory did. Only way to compare the old specs that were same for 20 years to the new specs for Winder clutch. This float deal sure seems to make sense. KnappAttack were you running a adjuster on your secondary?

 

[1nc 2000]