I just finished mine up on Thursday and it made a hell of a difference. Went on a short ride Friday then a all day ride Saturday.
Gas mileage is way better, engine braking is not as harsh, power delivery is much smoother, and it sounds better. My exhaust was also WAY off so there was really nowhere to go but up on performance.
Also, Jondog, do you remember how rich my bike smelled when we rode? That is gone.
There is a thread with members' valve clearance numbers somewhere around here. I plan to post up my numbers once I get back home.
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