01 yz 426 heat and idle issues HELP!!

6 replies to this topic
  • ezzrigby

Posted May 05, 2008 - 12:45 PM


I have a 01 426 been running badly after full strip down won't idle off choke at all, striped the carb down found the pilot valve(42) was bloked. Tried it again no joy. striped it again same fault but the carb is spotless. Cleaned it again and tried again(fitted an inline filter from the tank). Now it starts on choke but i have to adjust the idle knob alot to start it. Today i've got it to idle by adjusting the idle knob but if i stop it it won't restart without playing around with the idle knob!

When i did get it to idle the bike seemed to get mega hot, so much so the the front pipe of the exhaust changed colour (cherry)is this linked to my carb faults or is it something else or is it normal.

Anyone please help as i'm missing alot of good weekends riding at the moment:confused: :eek:

  • Stepdaddy

Posted May 05, 2008 - 12:56 PM


if your bike is sitting and running for more than a min. or two your pipe will glow....how long are you keeping the bike running without it moving?

  • bustersat

Posted May 05, 2008 - 12:58 PM


If it is getting that hot you are running lean. Don't do it for long or else you will miss a lot more weekends worth of riding. Check the jetting and make sure the carb is spit shined! Sounds like you are still having pilot issues!:eek:

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  • ezzrigby

Posted May 06, 2008 - 10:13 AM


Hi, yesterday was a hot day and i surpose it was running for maybe 2/3 mins at a rasied rpm trying to set the idle speed of choke. Will go back to the drawing board. I have the standard pilot jet fitted (42) but this seems to block very easily what can be getting past two filters?

  • zookrider98

Posted May 06, 2008 - 10:24 AM


Is your exhaust free of any debrit?

  • 426pilot

Posted May 06, 2008 - 03:49 PM


I'm curious what you mean by a full strip down? I replaced my stock piston with a Wiseco hi comp piston and immediately noticed the bike getting hot much more quickly than it did before the rebuild. If you're still running a stock piston, I'd suggest going over the carb with a "fine toothed comb". Make sure you use compressed air to blow out the passageways that control the choke. Best of luck to you... nothing's more frustrating than a carb problem.:eek:

  • ezzrigby

Posted May 07, 2008 - 09:22 AM


Hi fitted all new bottom end bearings and new piston kit(vertex) as standard spec kit. Basically had a total nut and bolt strip down every part stripped and cleaned and inspected. should of left well alone as it ran ok ish!!

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