need help 08 450

3 replies to this topic
  • mclean133

Posted April 13, 2011 - 03:06 PM


I have a 08 yzf 450 all stock with very low hour's. The problem is after the bike is started ( it starts 2nd kick every time and idle's fine) you give it a little bit of gas it start's to break up, pop, backback fire. Just like you would when you try to let the clutch out with a little gas. But if you cracked the throttle it doesn't do it is it a jetting issue i have cleaned all the jet's out checked every thing out it look's good.:thumbsup:

  • grayracer513

Posted April 13, 2011 - 03:45 PM


Did this start before or after you had the carb apart?

Did the bike sit for an extended period (60 days or more)?

Did you have the slide out?

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  • 2grimjim

Posted April 14, 2011 - 07:40 AM


Did this start before or after you had the carb apart?

Hehe! that's funny! I like the way you think.

IF you did have the carb apart make sure you (or someone else) assembled the slide correctly.

This is what you should see if the slide is assembled correctly, There should be a hole visiblein the back of the slide......
Posted Image

If is assembled upside down it will look like this......
Posted Image

The slide just falls apart when it it removed from the carb.
Posted Image

  • grayracer513

Posted April 14, 2011 - 01:52 PM


Nice pictures. Thanks.

Another point to check is the small seal that sits in a groove on the circular section of the slide plate. It is "tapered" in that there is a free edge of the sealing lip that is larger in diameter than the other edge. When properly placed, the small edge of the taper goes into the cavity in the slide first.

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