Question about 2003 KTM 640 Duke 2

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Was rideing and just stalled like it had no fuel!! but does have fuel. now i turn it over by electric start and is now back fireing threw the carbretor and blowing the carbretor off any one know wot this mite be thanx.brad.

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Clearly a valve issue. the valve that give gas and air to the chamber and closes in combustion may be damaged as it is letting the cumbustion out to the carb.

very dangerous i may say as the shraps from the carb will be a shotgun shots on your leg.

have this repaired as a new valve will be around 100-300$ depending on the brand and the condition. get an oem

Posted on Oct 06, 2009

Testimonial: "thanx alot my friend very helpfull.brad."

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