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Reading spark plug and popping on decel questions. Need quick answer

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Trying to do some quick matience and prepping before this weekend. Bike is apart in my garage and have a question I need answered quickly. Any ideas?

Got a brand spanking new plug here and my old one. Old one is black as night on the edges and brownish color between the spots where the spark is. Does that mean it's running rich or lean? 😢

Also I have a lot of popping on decel also. Same question. Does that mean I'm running to rich or lean? 😢

Thanks in advance 😢

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So the popping means it's rich also?

Thanks for the first response 😢

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O.K. so if I'm getting this correct I might want to tighten down the fuel screw and raise my main jet?

Maybe I should take this to the Jetting forum?

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Here's the fun part: If it's popping on deacceleration it's too lean.

or a exhaust leak

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Popping is lean, backfiring is rich.

Touching the main jet will do nothing at all. You will need to mess with the pilot jet, or the fuel screw.

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The main jet controlls about 3/4 - full throttle. The needle controlls about 1/4 to 3/4 and the pilot controlls the 0-1/4. The fuel screw controlls about 0 - 1/2 if I remember correctly.

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From idle to about one quarter throttle, you are on the pilot jet. 1/4 to a half (roughly) the needle and seat come into play. You are on the main jet when you are around half throttle or more.

This would be a prehistoric guide to jetting, as accelerator pumps and 'power now' valves are improvements in pumper carbs.

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It's too rich, but by turning in the screw, will make the like leaner,m your pops louder. You will need a bigger pilot if the pops get worse when you make the bike leaner.

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