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CRF 530, Jetting advice?

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Hi Guys,

Tomorrow me CRF 540 will be ready to start. It has:

99 mm bore (+3mm)

69.5 mm stroke (+7.4mm)

14:1 Compression

+2mm oversized valves

Carb bored 2mm larger

Yoshimura exhaust

I am at 800 feet and about 70 deg. F.

My question is where to start on jetting? What Pilot, Main, and Needle to use?

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This is a guess, so jet richer if you're uncertain-

#45PJ (stock '02 CRF)

1 1/2 turns out

Stock needle (OBEKR)

#4 clip position

#180 main jet (slightly bigger for the 2mm oversize)

Adjust the fuel screw as needed, then ride a short distance and check whether the response feels rich or lean and adjust as needed.

Sounds like a fun project bike! :thumbsup:

James

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I forgot to mention that I also have a JD Jetting kit to choose from for needles as well if one of those needles might work better.

Thanks

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