05 yz450 hard starting please help

1 reply to this topic
  • art_v

Posted October 28, 2010 - 03:07 PM


hi i just bought my first 4stroke a o5 yz450. the problem is that when i start my bike it will take a few kicks to get it started when could but when its hot it takes almost 20 kicks to start it and some times i would have to cleaned carbpull the choke out to get it to run then when i push it back in it would stall out but when it does fire back up it runs good till i turn it off and have to start it again also it will back fire and idle high oh and when i do turn it off it makes a weird sound out the exhaut like a quiet backfire this thing is driving me nuts what i have done so far to the bike is this

had valves adjusted

put in a bigger jet and the needle is 2 full turns out

also did not find an exhaust leak

thanks for any help kicking this thing over so many times is killing me lol

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  • kdub442

Posted October 29, 2010 - 01:29 PM


I had a problem getting mine started hot, but that wasn't my main complaint. It was the bog and stall with throttle chops and quick throttle. Sent the carb to Zipty for their racing mod. I think $125. Cured everything. Starts super easy now all the time. Watch out for the new found throttle response. I was doing the arm pump wave, and just touched the throttle without having a good grip. Sent me for a loop. Now when my hand touches the throttle it is with intent.

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