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.

A.Sailer95

Cam shaft question

5 posts in this topic

So I just rebuilt the top end of my 06 yz450f and fired it up and it ran for about 10 min then died so I pulled it apart again and the timing chain had a kink in it that I ended up being able to fix just by pressing on it with my hands. But now I'm putting it back together again and noticed that the lobes on the exhaust cam are way out of whack because usually when it's at tdc and timing is correct the lobes should be pointing outwards but I got the marks lined up but both the intake and exhaust lobes are pointing the same way. So clearly I need new camshafts now but my question is how did they get like that, and what else needs to be fixed/replaced so that it doesn't just happen again?ImageUploadedByThumper Talk1456112772.605950.jpg

Share this post


Link to post
Share on other sites

If your timing chain is kinking you really need to replace it! I just rebuilt one for a buddy his chain kept slipping teeth because it was worn and stretched. Looks to me like same is happening to you.

Share this post


Link to post
Share on other sites

If your timing chain is kinking you really need to replace it! I just rebuilt one for a buddy his chain kept slipping teeth because it was worn and stretched. Looks to me like same is happening to you.

Thanks! Any idea how the lobes would get shifted like that?

Share this post


Link to post
Share on other sites

The sprockets are pressed on.  They very rarely slip, and almost never that much.  Usually see this sort of thing when a camshaft seizes to the head.  Any evidence of damage to the cam bearing areas? 

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