crf 450 jetting

now has

172 main

45 pilot

NJES needle 3rd clip from bottom

Adjusted needle, 2nd clip from bottom it was rich and sputtered ( or how ever its spelled)

3rd clip from bottom was ok. Just thinking I'm missing some power at mid range so is it ok to go one clip leaner? How I can notice its too lean?

And which way is good to find correct main jet. Had 178, then 175 and now the 172. No much difference. Even with 178 ran clean at full throttle. Well the plug reading worked well with smoker but I feel like it doesnt make the best results with 4 stroke.

Also needle has 5 positions. Somebody have some info about this needle? I just dont find any.

Even a 172 is a large main jet. I would try a 165.

Do not fret going too lean, no damage will result. One of the beauties of a $S is they can handle being so lean they will barely run and no damage will result.

What year bike ? That would help us help you.

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