Primary Clutch.....Belt travel height?

[RTX Meirda]

How high should the belt travel up the primary clutch sheeves without having consequences.

I marked the sheeves with a magic marker.

I think it would be safe for the belt to travel higher?

 

[Frostbite]

I think a good rule of thumb is 1/4" from the top is about as high as most of us will ever see without machine work.

Frosty

 

[RTX Meirda]

Yes....exactly what I am seeing.

 

[Frostbite]

Then you are there! I wonder if you put thinner split collars in (and the clutch faces come closer together) if it would climb any higher?

Frosty

 

[Blue shadow]

You can change the split collars and have the same results .You have to machine your clutch to get the belt to go up higher.Take your primary spring out and put your cover back on and press your clutch in.Take your belt and let it sit on top and then you will see what you have left.

 

[Buckeye]

Then you are there! I wonder if you put thinner split collars in (and the clutch faces come closer together) if it would climb any higher?

Frosty

No! The split collars impact engagement not full shift. The sheaves will touch at the bottom with stock thickness collars.

 

[RTX Meirda]

I work beside a machine shop....what do I need to do?

 

[Buckeye]

You need to remove material from the lower portion of the sheaves, so that their tops move closer together. You will also need thiner split collars to compensate for this change.

 

[Sled Dog]

Could you not run a 1/8" wider belt to get it to run higher. The higher on the primary will mean the belt will have to run lower on secondary giving you the equivalent of a passing gear. As long as you have the HP to carry the sled to the speed so that the weights can squeeze that belt enough it should work.

 

[LightningPro]

BlueShadow is correct about the sheave not coming any closer. If you have access to a machine shop, face off .015 of the point of contact of the two sheaves and .015 off the wide side face of the split collars. On the lathe blend a radius on the sheave face from the new flat created. Also the clutch should be re-balanced because the removeable sheave will rotate back on to a new position. You should also consider the secondary will also need to be able to shift further. Stock helixs can/will stop short and you can/will break a belt at extended high speed. Aftermarket helixs might shift further. Most aftermarket secondaries will accomodate the overdrive shift. Shorten the inner hub of a stock helix or machine the outer hub face on the stock secondary (very hard steel material to machine) This mod is not for everyone and shouldn't done unless all steps are done.