burning spark plugs?

i got a question, its probably pretty dumb, but why do my spark plugs get soo dark and black soo fast. itll only take like 20 miles and its real drak. thanks

Re: burning spark plugs?

your bike is running too rich, try cleaning your air filter, and adjusting the mixture screw (if your bikes carb has one, most moped carbs dont, some do though) if it dosent have one and the air filter is clean, try buying a smaller main jet, also clean out your airbox while your at it, it may need cleaning as well. anyway, its somthing keeping good air flow from reaching your carburator, causing the mixture to be too rich on fuel, not enough air, making the mixture very oiliy, fouling up your plug quickly with a nasty oiliy slick. when its running on the proper mix, your spark plug tip will be dark brown/tan like the color of coffee.


Re: Could also be

Check the float and needle to be sure the float hasn't sprung a leak, and that the needle seats properly on the seat.

Don't chnge jets til the obvious and common problems are eliminated.

Running rich comes from not enough air, or too much fuel.


Re: Could also be

Mo need to buy a jet. take the top off the carb, and there should be a slide valve there, with a silver pin on the bottom. If there isn't, ignore my advice. Take out the silver pin. You will see notches at the top. There will be a c-clip in one of the slots. to lean the mixture, move the clip up a few slots. do a plug chop, and keep adjusting the mixture un till you get it right or run out of slots. (then it's time to buy a new jet.) To make the mixture rich, reverse my procedure. move the clip down.

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