Question about 2003 Yamaha YZ 250

1 Answer

Bike loses power in the mid rpm range

It rides fine at low rpms and good and high but there is just no mid range power it feels like it just doesn't want to run.

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  • Paul G
    Paul G May 11, 2010

    Hi before i can help you i need to know ,
    Does it cut out on you when in midrange ?
    when was the last time you had the jets reset in the carb?
    what kind of fuel oil mix are you using ?
    when was the last time you cleaned the air filter?


    Regards


    roadrunning1

  • larry blais
    larry blais May 11, 2010

    Is the bike stock, has it been jetted or chipped.

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Try the air filter first (make sure it's clean). The needle valve on your carb slider could be bent, or not seated correctly or just set wrong. If you have a power exhaust valve, it could be set wrong or malfunctioning as well. Good luck.

Posted on Jun 25, 2009

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1 Answer

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