cam adjustment

How do I adjust the cams on a 2003 Wr 450 (or YZ 450) ?

There is no E and I like in the 1998 - 2002 models, so am I supposed to use the 0900 and 0300 dots for alignment ?

That's what I am doing, but it's not working (not enough compression).

Thanks.

If the intake has no I or E stampings, then yes, arrange the marks at 9:00, 12:00, and 3:00, and use the 3:00 mark to time the intake. The exhaust has only two marks. Arrange them at 9:00 and 12:00, and use the 9:00.

DO NOT attempt to set a WR450's cam timing to YZ specs, or vice-versa, as you were able to do with the 400/426 because to do so will throw off the timing of the decompression mechanism to the point that the engine won't develop enough compression to start.

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