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Did the power up conversion on my son's 150 and, due to inexperience, failed to change the pilot jet.

I had no problems with the needle or the main jet, but have no idea where the pilot jet goes. Is that part of the long stem that the main jet connects to?

I'm going to tear it apart and will probably eventually find it. Just wanted to post the question in case I get stumped.

Also, what about the air/fuel screws on the carb. There are a couple screws on the carb. Which one is which and what are the typical indicators that I may have one or the other misadjusted?

Thx.

Did you find it and where is it. I am working on my sons 150F and have the same question

Hi Don,

I hope this picture will help you. The pilot or slow jet is long and thin and the main jet is short and wide.



good luck!

ken

Unlike my 450X, this carb requires one to take off the bottom bowl of the carburetor to access the pilot jet. It took longer than usual to start due to the lack of gas in the carb but a noticeable difference in power was achieved in rejetting.
CRF150F:
Twin Air
Air box plug removed
Exhaust diffuser removed
stock 98 main changed to 115
stock 40 pilot changed to 42
stock needle changed to 16012-KPT-921 (3rd from top)
Next step and hopefully last is Big Gun Evo X
My wife keeps asking why these new bikes keep breaking down!!!

Don,

Get her one of her own, then she'll be just as hooked as the rest of us!