Valve Adjustment Question

A friend is about to buy a CRF450 for his motocross campaign and trail riding. He is new to TT and having some problems posting so here goes.

In the past there have been posts about the need for frequent valve adjustments, replacing the head, Valve recession.

Is this anything to worry about with the new 03 model?

I suggested he check the valves when new, Make note of the shims that are in there, and buy incremental shims so when the valves do need reshimming he has the next couple of sizes to get the job done. Keep records, checking frequently and then he can get an idea of whow long between adjustments. That is basically what I have done in the past on Suzukies with the same setup.

Also is there a connection between the air filter leaking problem and intake valve wear that has been posted in the past? Has the air filter been modified on the 03?

I am waiting for a 6 speed 450 with lights before I make the switch back to Honda as I only trail ride my KTM.

The couple of 450f I did ride at the track felt more stable than my 98 cr250 and I can hardly wait for the trail model.

Thanks in advance for your advice..

I got my 03' back in July of 02'. I ride it about 3 to 4 hours per week and now have 60+ hours on it. I have only needed to shim the valves one time. It only takes me about 3 days to get shims from my dealer ($5 each) so I just measured to see what I needed, put it back together, and rode until I got the chance to put the new shims in. I would just do this unless the clearance is less than 0.002 at which point I would not ride until fixed. I keep hoping they don't "go to zero" all at once as some here on TT have had happen on their 02's.

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