2003 YZ450F New owner

6 replies to this topic
  • zimak

Posted February 01, 2008 - 07:52 AM


Hi guys, I'm helping a friend setup and inspect a 2003 YZ450F he just picked up this week.
First owner dumped a ton of money in it and sold it.
Second owner never did any maintenance just rode it 2-3 times and garaged it.

Starts 1-2 kick when cold and 1st kick every time when warm. Some minor gremlins we've found and are fixing (parts on order) but here is one thats got me confused.

Went to check and adjust valves last night and here is what I found when trying to get it to TDC.

Posted Image

....its not supposed to look like that is it? Any idea what part and part numbers I'm missing?

  • TD-3

Posted February 01, 2008 - 07:57 AM


Looks like an aftermarket flywheel weight, sans timing mark. You'll have to find TDC and mark it yourself.

  • TD-3

Posted February 01, 2008 - 07:59 AM


Also, the breather tube is kinda pinched in the bottom clamp, you may want to re-route that higher on the frame.

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  • zimak

Posted February 01, 2008 - 08:14 AM


Ok so short version, how do I find TDC compression stroke to mark it so that it aligns in the window?

  • TD-3

Posted February 01, 2008 - 08:29 AM



  • grayracer513

Posted February 01, 2008 - 09:55 AM


You WILL want to fix the breather tube, or you may be introduced to the fabulous ejected decomp bore plug, as well. This is an early YZ450 tradition you can do without:


  • mxdad32

Posted February 01, 2008 - 10:04 AM


It looks as if the first owner marked it with a perm. marker if you look in the center hole. Unless that is a mark you put there.

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