02 Yz426 slipping?

[LancoRider726]

Hey I have a 2002 yz426f. Bought it a few days back. I was riding on some trails and took a short cut on a road back to the truck and trailer. When I got up into 5th and rolled on up to about 3/4 throttle, the bike started to skip. As if the chain had a bad kink or somthing like that. My buddy said just put a new clutch in it but I didn't wanna spend 60+ and that not be the problem. Thanks for any input.

[grayracer513]

The most likely cause is a worn set of locking lugs on the 3rd and 5th main shaft gears (pinions). They get rounded over and will no longer hold in under a load. As they force themselves out of engagement, they bend the shift fork as well.

[LancoRider726]

fml. Its very harmonic. Happens about every second.

[grayracer513]

It's not the clutch. It only happens in 5th, right?

It's the transmission.

[09speeddemon]

If it does it in other gears check your sprockets and make sure the teeth are not rounded or broken.