06 yzf450 Help cant Figure it out.

7 replies to this topic
  • Vince911

Posted March 08, 2012 - 12:02 PM


So my customer brought in an 06yzf450. It acts like its running really lean. Backfiring, popping, shooting flames. With a minute or less its hot. I changed the gas. Changed the jetting. Adjusted the valves. Correct timming. Checked for an air leak. I can not figure it out. Nothing seemed to help. He does not want me to pull the head due to money. There is a rattle you can hear from time to time you can when kicking it over. So im sure its about to go. Any ideas or suggestions would be helpful.

  • cowboyona426

Posted March 08, 2012 - 12:08 PM


Is the plate in the carb slide in upside down?

  • Vince911

Posted March 08, 2012 - 12:16 PM


Nope its in right.

  • Vince911

Posted March 08, 2012 - 12:24 PM


Checked and adjusted hot start and enrichner.

Visit the ThumperTalk Store for the lowest prices on motorcycle / ATV parts and accessories - Guaranteed
  • CO_Rider

Posted March 08, 2012 - 02:53 PM


Not to second guess but I would check the valve clearence again. Just sounds like the symptoms. Have you checked out the exhaust packing?

  • Chas_M

Posted March 09, 2012 - 07:36 AM


Have you checked to make sure that the idle circuit is working properly? Have you cleaned or replaced the pilot jet?


Posted March 10, 2012 - 08:43 PM


Checked and adjusted hot start and enrichner.

Replace the o ring gasket on the slide plate and make sure the plate intself isn't cracked. Use a magnifying glass and make sure! I have fixed several yz's that have had the same problem, and also make sure the acc pump nozzle is squirting fuel!

Edited by CROGGR, March 10, 2012 - 08:43 PM.

  • yz450fcranker

Posted March 13, 2012 - 12:56 PM


open her up she might want a rebuild

Related Content


yz250x vs 450 4t comparisons (preferably desert riding) needed by JakeNorthrupYZ450F

Dirt Bike   Make / Model Specific   Yamaha   Yamaha 2-Stroke
  • 9 replies

Thinking about Yamaha 250... by Arctic Pride

Dirt Bike   Special Interest Forums   Pro Racing
  • Hot  491 replies
WR Camshaft Swap Info - last post by jamesm113

WR Camshaft Swap Info

  • 0 replies

James Stewart back on a YZ450F by YamaLink

Dirt Bike   Special Interest Forums   Pro Racing
  • Hot  47 replies

Wilson the Blue Privateer by jetfuel

Dirt Bike   Special Interest Forums   Pro Racing
  • Hot  50 replies

Join Our Community!

Even if you don't want to post, registered members get access to tools that make finding & following the good stuff easier.

If you enjoyed reading about "" here in the ThumperTalk archive, you'll LOVE our community. Come join ThumperTalk today!

The views and opinions expressed on this page are strictly those of the author, and have not been reviewed or approved by ThumperTalk.