YZ 400 F carburation??

2 replies to this topic
  • c-man

Posted August 08, 2002 - 05:41 AM


This may be a worn out topic to some long-standing TT members, but I am new to TT and would like some input on the topic. I have had my 99'400F for 2 years and would never go back to a 2-stroke again. I love it!! My father (56 years old) liked mine so much that he went out and bought a new 2001 holdover. I have noticed that my bike idles a lot rougher than his, and somewhat rougher than other 98 & 99 F's that I have seen. Has anyone else had this problem, and if so, what can be done about it. It is somewhat annoying when you have to throttle it up at idle to keep it going, or adjust the idle screw to get it to idle right, and then it will race at idle after running it hard and then slowing down! I would appreciate input on this topic. Thanks! P.S. I get a kick out of reading some of your topics of discussion. :)

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Posted August 08, 2002 - 07:12 AM


The over run (High Idle) is caused by mis-jetting. Take a look at my YZ jetting in the signature below. This jetting is good for sea level to 6000 ft (tested)


  • Dodger

Posted August 08, 2002 - 07:57 AM


A good carb cleaning never hurt anything or anyone........just an idea :) .

Dodger :D :D


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