YZ450F mystery part?!

7 replies to this topic
  • rcvxl14

Posted March 14, 2015 - 07:27 AM


I'm finishing up the top end on my '09 YZ450F and I can't for the life of me figure out where this little spring goes. I searched parts schematics and the service manual with no luck. Anybody have a clue what it is, and/or where it goes? I think I remember pulling it out of the head or jug somewhere but it was so long ago I can't remember.


ImageUploadedByThumper Talk1426346704.826441.jpg

  • cjjeepercreeper

Posted March 14, 2015 - 07:29 AM


Does that bike have an auto compression release?  If so, it looks like it could be a part of that, there is a spring in there in the head for that function.

  • rcvxl14

Posted March 14, 2015 - 07:42 AM


The decompression mechanism is on the exhaust cam, so I don't think that's it. Thanks for the quick reply though.

  • torkd14

Posted March 14, 2015 - 08:39 AM


Timing chain tensioner maybe?

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  • rcvxl14

Posted March 14, 2015 - 10:55 AM


Nope, not that.

  • kurtcrf450

Posted March 14, 2015 - 11:06 AM


Post in the yz450 forum and grayracer will probably know right away

  • billygildark5007

Posted March 14, 2015 - 01:34 PM


Plunger assembly from hot start cable?

  • rcvxl14

Posted March 14, 2015 - 01:50 PM


Well i just solved the problem haha. It turns out it was the internal spring off of a female air hose end, and it somehow got tossed in my parts box! Makes feel pretty stupid haha, but thanks for the replies!

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