QuestionQUESTION: Hi, I have a 750cc virago that builds carbon in the spar plugs every time I use it, and I have to replace them every 70km. The carburetors has being cleaned twice, someone told me that the left cylinder is starting to go bad, it has less pressure but still runs, should I keep riding or I could damage the engine? if the cylinder needs to be rebuilt how much this should cost?
ANSWER: Ar eboth plugs fouling? if it is only one, it could be valve seals or rings, does the engine smoke? Let me know if it smokes under acceleration or when you release the throttle are higher revs. Let me know,
Jan
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QUESTION: Yes both plugs build carbon, with the bike in neutral I accelerate and once in a while shoots very black smoke, and on the roads if I go in a short gear is no to good, when I accelerate strongly some times shots a bit of flame and farts loud, when I release the throttle and ride in 4th o 5th gear sounds better.
AnswerSounds like your valves are not seating. Best thing to do is a compression test, also check if the crankcase is building up pressure by feeling the crankcase vent. The compression test should give results around 140-190psi and the readings should be the same. Within 10% anyway.
Good luck, Jan
