Question about 2005 Yamaha XT 125 X

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I have a 1983 Yamaha DT125K On/off road motorcycle. I just rebuilt carb although when it is running it idles fine. If I increase RPM the motor begins to starve. I am assuming the float is not set properly and there is not enough fuel to supply the required fuel.

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Yes, check float level, also make sure the slide needle is anchored under the return spring. Also check the air mixture screw. start by turning idle mixture screw in until it seats,(lightly), then turn it out 1-1/2 to 1-3/4 turns. While engine is idling, turn the screw in or out to achieve the fastest rpm, re-set idle to normal

Posted on Nov 02, 2010

  • jimrcowden85 Jun 09, 2011

    i have a 1985 dt125 it does the same runs perfect from cold,soon as theres heat in the engine when i try to give it high rpm it sounds like its starvin? iv tried the mixture screw and also replaced the air filter and spark plug,and also the ht lead has been replaced with a rubber plug and gel insets,this still hsnt cured the problem.



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