HEADS UP!!!

Site upgrade in progress... Core site functions are working, but some non-critical features/functions will be temporarily unavailable while we work to restore them over the next couple of weeks.

Please post any bugs you encounter, but before you do, check to see if it's already listed.

Thanks for your patience while we work to improve the community.

Sign in to follow this  
Followers 0
finthat

Clutch or gears

6 posts in this topic

I have a 03 yz450f that I just rebuilt the whole thing after the previous owner airated the crankcase via connecting rod. Had cases repaired, replaced all tranny bearings, crank ect. Had to buy a different set of used trans gears as the big end bearng went through the old one when it scattered.

The bike runs great shifts good ect. My issue is it seems to slip under hard acceleration in 4th gear. No issues in 1, 2 or 3. The clutch look pretty good to me when it was apart, nothing warped or burnt ect.

Do I have a clutch problem or a 4th gear problem?? Any of the used parts I put in looked to be in decent shape. I have about 12 hrs on the fresh engine problem doesn't seem any worse or better. Don't want to tear it all down if I don't have to.

Share this post


Link to post
Share on other sites

Thanks. I think I have a trans problem. My clutch does have free play on it and it is a very fast rise in rpm then when I back off a just a little it goes bakc in. As I increase speed it get easier to make it do that. Would keeping pressure on the shifter while accelerating help diagnose the problem as in hold it in gear or feel some feed back on the shifter?

Share this post


Link to post
Share on other sites
Would keeping pressure on the shifter while accelerating help diagnose the problem as in hold it in gear or feel some feed back on the shifter?
Maybe. But even if the gear pushes itself out of engagement against the fork, it still cannot cause the shift cam to rotate as the fork cannot drive the cam. The feedback would be somewhat indirect. If you absolutely cannot make it do this in any gear but one in particular, that's another sign.

Clutch slip is more like a tire slipping in poor traction, except it happens more in the higher gears than the lower ones.

Share this post


Link to post
Share on other sites

Clutch slip is more like a tire slipping in poor traction, except it happens more in the higher gears than the lower ones.

Thanks man. I think I will be splitting cases. Mine problem is a for sure on and off. I revs up and re-hooks almost instantaneously like an on off switch.

Gears and forks for sure then? If I remember my gears looked not to bad when it was apart this winter. Or is doing both just a good way to be sure?

Share this post


Link to post
Share on other sites

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!


Register a new account

Sign in

Already have an account? Sign in here.


Sign In Now
Sign in to follow this  
Followers 0