Question about 2003 Yamaha YZ 125

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Can not start

My sons yamaha 125ttr will not start his friend road in second gear for 15 min then smoke was coming out of hose on bottom now can not start son said he turned screw on carborator set screw in now how many turns out

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Remove the float bowl and clean the entire carb with a spray carb cleaner from the auto parts store. Wear protective goggles to avoid getting spray in your eyes. Spray into all the little airways and fittings in the carb. Remove the two screws, ( idle and air screws ), on the outside throat of the carb and spray into the screw holes as well.
Be sure to put these two screws back in the same hole they came out of. IMPORTANT > do not tighten these two screws down. Only screw these in until they LIGHTLY seat. Now turn each screw one and one half turns outward. Put the rest of the
carb back together, clean the air filter and install the carb. Let the float bowl fill then start the engine.

Change gearbox oil. 10w40 is what is needed. Also install a new stock NGK spark plug. This process should get you back on the road.

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Posted on Apr 17, 2009


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