Jetting issue with 03 yz450f

Hello all, I have a 2003 yz450f I believe I have a jetting problem but not for sure. I'm at 6,400 feet elevation and I have my needle clip on 3rd notch main jet is a 165 and pilot 42... When I am at wide open throttle it feels almost like my clutch lever gets pulled in then released real quick... It'll do this more and more the faster I get going.. Any ideas?

Are you sure it's not just your clutch slipping?

Do the rpm's jump?


There is no reason to suspect jetting if the bike ran well with the jetting you now have, at one time.


More likely a bad plug or before the plug.

Yes the rpms do jump a little within that second then it'll jerk forward once it grabs again.

So would you suggest that I check my clutch plates to see if the friction plate material is gone?

Yes your problem is drivetrain.

Stop riding it and take of the clutch cover and inspect.

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