YZ 426 timing chain

I have a YZ 426 and there is a rattling noise coming from what i think is the timing chain. Its a 2001 model and i bought it used about 2 years ago.  How often should the timing chain be replaced, and could this be the problem.   

post a video clip of it running it will help

grayracer is a wizard on these kinds of things maybe he will chime in. In the past I herd things like put a hand on the skid plate or rear shock spring to see if it stops the rattling sound another one is kicker gear staying engaged ?. pop the valve cover and just see if the timing chain is lose?  take off both side covers and check fore something loose? . Maybe its internal like the rod bearing on the big end or a crank bearing-I,m just guessing but I think its like a ticking time bomb

I've checked all of the external parts on the bike and also checked the clutch. I thought it might be the timing chain or the tensioner. Thats where im looking next. I went on YouTube and it sounds like others have the same noise.

I have a little ratle noise also but i think its normal.

How long have you owned the bike? I just started riding the bike for the last two seasons and didn't notice it until this last summer.

2 years and still got the bike

of the 3 that I have had I never had noise like that in your video out of them I usualy run 15/40 in them what weigh oil are you using?

The same as you

think its time to tear into that engine,dosen't sound normal to me.

grayracer is a wizard on these kinds of things maybe he will chime in.


Actually, I can't normally tell anything from the sound recordings people post of their bikes.  The sound quality is normally so poor that I can't determine anything about it, particularly with all the racket these things make when they're perfectly healthy.  Yours is pretty good, compared, but the only thing I heard was it sounds like it's running a little fast.


Timing chains should be replaced annually or thereabouts as maintenance.

just because you have not put in a chain do it, and shim the valves while your in their and run it and hope for the best ?

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