Question about 2003 Yamaha WR 450 F

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My 03 wr450f ran fine for me last summer...i let it set for a good 6 months...went to crank it the other day... I do race it and it still will fly on top end speeds but it will hardly idle now and back fires sort of like a miss....with choke does not smoke I changed the plugdrained the gassprayed alittle carb cleaner in the fuel line before cranking and taped the bowl ran alittle better but still is not my old bike... Does this sound like carb problem to you...this bike has been very dependable till now.. When I first cranked it it would only idel with choke on... Thanks for your time....mike Wilson

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Yes you will need to remove and clean the carb, fuel will have left sediment after 6 months

Posted on May 17, 2010

  • Graeme Scott Aug 08, 2011

    More specifically if it will idle on choke and not or badly with the choke off, then probably the pilot jet is blocked.



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My 03 wr450f ran fine for me last summer...I let it set for a good 6 months...went to crank it the other day... I do race it and it still will fly on top end speeds but it will hardly idle now and back...

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