'00 YZ426 exhaust cam (chain stretch)

Putting the bike back together after some new valve shims, it appears I have a bit of stretch in the timing chain.

The punch mark on the 'I' side of the intake cam aligns perfectly with the top of the cylinder, but i have a choice of half a tooth above or below the cylinder for the punch mark on the 'E' side of the exhaust cam. (All valve train components are stock)

Would one be preferred over the other (slightly advance or retard the exhaust cam)?

I've done a search, but haven't found the specific answer. Much thanks!

If it's not a new chain and you feel that it's stretched(definately if it's the original) why not just replace it with a new one...And a tensioner ....alot cheaper than the repairs from a chain failure...But that's Just my opinion

You're definitely right, but i was hoping to ride this weekend, which is why i'm pushing to get it back together with the parts i have.

i hear ya on wanting to ride...we got 2' of snow last weekend....and another 12-18" coming....maybe someone else can chime in with a suggestion on which way to go..good luck

replace the chain and tensioner or this weekend will be the last weekend you will ride it. $50 in parts is not worth toastin the motor and personally i would rather wait a week than blow mine up.

is this with tensioner installed? If not much just be slack, put E cam on the mark and I cam slightly above and install tensioner, rotate engine 2 revolutions and recheck.

Yes, this was with tensioner installed and rotated multiple times, thanks for the advice. It's back together with I cam on the mark and E cam just slightly retarded (half a tooth).

I'll let everyone know if i run into problems. Check, on the fact i need a new one....

Yes, this was with tensioner installed and rotated multiple times, thanks for the advice. It's back together with I cam on the mark and E cam just slightly retarded (half a tooth).

I'll let everyone know if i run into problems. Check, on the fact i need a new one....

well damn good luck!

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