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JD, quck question. . .

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I need your advice. Athena big bore kit with stock jetting= very rich, sooty plug, won't start. Ended up with a 160 main (down from 165), one leaner pilot from stock (40, or 42, I forget!), and 1 turn out on fuel screw. Bike ran great, but seemed to run hot, spew a lot of coolant. Installed a stage 1 Hot cam. Bike was way lean with these carb settings. Went back to stock jetting, fuel screw 1 3/4 turns out, and clip one position richer than stock. Bike runs strong off the bottom, no hesitation, easy starting. Should I try a 168 main to see if it helps when I'm wide open, or should I just stick with what I have now? Haven't had the chance to open her up wide open yet, but half throttle seems okay.

Thanks for the help.

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Stay with the #165 and ride it. A smaller main jet is more often needed with a big-bore kit. Judge the top-end power as you ride and then consider if it needs to be richened.

James

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James, I pulled my plug today and it was black and sooty after a day of riding MX. This was my first real track run with the Stage on Hot Cam along with my big bore kit. The power felt good, no hesitation off the bottom. Where should I start? Put the clip back to stock position, or go one main leaner? Thanks again. Ps. I found I had a head gasket leak causing constant boil-overs, could this be the cause of the black plug?

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Go 1 clip position leaner on the needle and turn the fuel screw inwards 1/4 turn. Keep the #42PJ and #165 main with stock needle.

James

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I had my first real ride with the new settings today. Bike felt great after a little fuel screw tweaking. Pulled the plug after practice and it was a nice tan color. Thanks again JD. :cry:

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