04 YZ450F Leaking Oil

3 replies to this topic
  • c_spingola

Posted June 02, 2008 - 10:33 AM


At a race this weekend after the second moto the engine started leaking oil out of the front of the head near the exhaust. I have heard that there is a plastic cap that acts as a cap for the old manual decompression lever on the older 450's. Has anyone else had this problem and how did you keep this cap attached after it blew out? Any help would be appreciated.



  • grayracer513

Posted June 02, 2008 - 10:43 AM


From the Common Threads Sticky:


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

Posted June 03, 2008 - 03:32 AM


Thanks for the info. I looked at the TT store and could not find the bore plug. Can you give me a link to the product?

  • grayracer513

Posted June 03, 2008 - 05:11 AM


TT no longer sells the plugs. They are still available on eBay in a couple of different configurations, or you can use an 18mm expansion plug (freeze plug, cup plug) from an auto parts store.

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