Different Primary clutch assy ?

[highpockets]

It appears the Yamaha primary clutches have some cracking issues ? Would it be wise on a turbo RX to switch out a cracked/damaged primary to,say,a Polaris P85 or some other type of clutch or merely rebuild(replace the sheaves on the existing yami clutch ? At this time there are some minute,almost appearance cracks at the bottom of the sheave as well as a groove worn in the sheave as if the sled was left idling for a long period of time ? I am just not comfortable with building the motor and bolting a clutch back on that might cause issues or even come apart. Thanks !

 

[Turk]

The cracking is due to heat issues with improper clutching causing belt heat. The small cracks at the bottom are normal & so are the grooves. I have put on a lot of miles on a clutch that has the small inner cracks on the shives. Only replace when the cracks spread across the faces...immediately.
If you feel comfortable you can buy a good used clutch for cheapish(200ish) & if your using aftermarket weights then 1 from any 2 stroke will work.

 

[highpockets]

Thank you,I can chalk that off my list for now and move on to other issues ! Should/could I have the sheaves machined or is there not enough surface area to do this ? Or is the small groove in the bottom not really a bis issue either ?

 

[Turk]

I see a lot of clutches in a winter & a lot of em have those small grooves & cracks. Just keep your eye on em & make sure they don,t migrate up the faces. I know that won,t help ya if your 20 miles in the back country but maybe look for a good used one & keep yours for a spare.

 

[highpockets]

I tend to watch it very close,not really into dragging the beast 15miles back to the trailer !