YZ timing mod on WR426

I've seen a few posts saying to mod the WR426 w/YZ timing but can someone who's done this describe it? Meaning, what is the benefit, what is involved in changing it, and is that a main diff betw a WRF and a YZF? Do a lot of you prefer stock WR timing?

I had the fortunate opportunity to ride my bike (WR timed at the time) on a single track trail, then hop off it and ride the exact same bike with YZ timing. I got off and he asked, "Did you like it." I said, "NO! (because I told him I had no desire to change) but when can you do mine." I really noticed that it revved out quicker. Some complaints were that the WR stalled in the tight stuff with the YZ timing... can you say "clutch control?" I didn't see much of a change in that area.

YZ time it!!!!!!!!


Go here. Motoman393 Site

I changed and the bike is a lot more fun to ride. Revs quicker, runs smoother and I don't think I lost any bottom end.

I agree with everyone else. I just YZ timed mine 2 months ago. Very noticeable difference. Souded better, ran better, quicker throttle response. Just more eager to get going. I have not noticed any issues with stalling.

See the motoman website. IMO you do not need to remove the cam chain tensioner.

Have fun with it.

I think you could also do this without removing the exhaust cam. Just mark the chain and cam with white out, loosen the tensioner, lift the chain and rotate the cam 1 tooth. :)

On mine, there would have been no way to rotate the exhaust cam without removing it. There just wasn't enough clearance.

If you could do that, it sure would be nice.

you won't have enough chain length to move the timing one tooth without removing the camshaft. As I found with my engine, the TDC mark isn't always perfect. It's a good idea to check that too :)


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