Im a little confused?? WR450 timing

I have been looking thru posts on the WR 450, and I am a little confused, Do I have to buy a yz exhaust cam, or can I move the WR cam one tooth like my WR400?? I have read posts that are conflicting, or maybe I am just dumb. Also, does anyone have a pic of where the grey wire is on the WR450?? I can't leave well enough alone, I have no miles on this thing, and am already modifying!! After I open up the airbox, and uncork, I will need to jet to 160 main, and 40 pilot, to be in the ball park, at around sea level , correct?? Thanks in advance for the replies!!

Dave VanBrocklin

Good question VB! I thought the wr/yz were the same this year in that respect but have also read the posts you're talking about. Does this mean there's even more power avalable from the wr? I don't really want to dig that far into the motor though. Does anybody know the answer to this one?

I think you ment a 48 PJ.

The grey wire is an easy solution. check the thread below and look for link in to the photo

Grey wire WR450 photo is in here

Changing the WR450 to YZ timing has not been completely cleared up yet. The issue is the autodecomp on the exhaust cam. On the 426 is was just a matter of changing the exhaust cam position by on sprocket tooth and you have YZ timing. With the WR450 cam doing this one tooth trick will also change the timing of the autodecomp. Some folks guess the WR450 won't be able to electric start with the exhaust cam timing changed by one tooth.

Maybe someone should ask how many of the sheared woodruff keys have been on WR450's with YZ timing on the exhaust cams.

Is there already a definitive answer to the question??

Can we do the wr/yz timing change or do we need a new cam??

Who nows more??


You need a new YZ 450 exhaust cam and reshim during install beacuse of the auto decompression feature on the 2003 YZ's & WR's.

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