99YZ400Starting/ running prob

2 replies to this topic
  • plew

Posted March 04, 2002 - 05:36 PM


My 99 YZ400 won't continue to run after the choke is turned off but starts fine, only if the choke is on. The bike has sat for a year with fuel in it. I know I f***ed up. Well I've drained the carb, put fresh fuel in it, oil/filter and coolant change. Any HELPFULL suggestions?
P Lewis

[ March 04, 2002: Message edited by: plew ]

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  • sbohanon

Posted March 05, 2002 - 02:06 AM


is the air filter clean, try starting without it.
turn the idle up??? if none of these work, clean the carb. probably buildup in the jets.

  • #302

Posted March 05, 2002 - 06:35 AM


Because of evaperating fuel that sits inside the carb for extended periods of time the fuel becomes a gel or even solid. The only fix for this is to take the carb out of the bike and clean out the jets. The jets have very small holes for the gas to flow through and when the fuel becomes a little crusty it clogs these small holes. From what you are describing it seems that your pilot jet is clogged.

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