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motokid338

Help!!!!

8 posts in this topic

I have a 2003 yz450f and it has a really hard time starting. once it starts it will not idle. then when it shuts off it's really hard to restart. It has a hot start but doesnt seem to help. I drained the carburetaor of old gas, cleaned the air filter i dont know what more i can do, the only way it will strat in the first place is of i open the throttle when im kicking. Any advice

:thumbsup::ride:

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Turn the idle screw up. It sounds like the idle is turned way down. Are you using the choke to start it? You shouldn't have to give it any gas to start it...

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Turn the idle screw up. It sounds like the idle is turned way down. Are you using the choke to start it? You shouldn't have to give it any gas to start it...

i dont know why i have to give it gas but i tried just using the choke and nothing happend in about 10 kicks so i gave it some gas and it started in 2 :thumbsup:

the valves are after market i tihnk their kibblewhite :ride:

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As previously said, check the valves, alot of high rpm, or hours, can tulip the valves, and cause hard starting. check the valve clearances, if there isn't any clearance or very little on the intake valves you need a valve job. mike

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their fairly new valves i think they might have 5 hours on them but i will see what they look.

i do get it started sometimes but it is extremely hard to start cold and even harder to start hot and i do have a hot start so i know it's not vapor lock. it only stays running for about 3-5 minutes and will not idle at all. ive tried adjusting the idle screw and the gas intake screw while its running and it just won't idle. i tried to start it today and i gtave it 12 kicks and nothing happened i also put in 93 octane fuel instead of 83 but ut just doesnt want to start. it's going to the dealer tommrow but im out of ideas :applause::thumbsup::ride:

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their fairly new valves i think they might have 5 hours on them but i will see what they look.

i do get it started sometimes but it is extremely hard to start cold and even harder to start hot and i do have a hot start so i know it's not vapor lock. it only stays running for about 3-5 minutes and will not idle at all. ive tried adjusting the idle screw and the gas intake screw while its running and it just won't idle. i tried to start it today and i gtave it 12 kicks and nothing happened i also put in 93 octane fuel instead of 83 but ut just doesnt want to start. it's going to the dealer tommrow but im out of ideas :applause::thumbsup::ride:

Did you're fuel screw fall out? Check valve clearances if you haven't already!

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