How difficult is it to do the yz timing?

How difficult is it to change the timing to that of the yz, and how does it affect the bike. Does this mod diminish the reliability or long term durability of the bike? Thanks in Advance

Depends on how mechanically inclined your are. You'll have to remove all parts around the cam cover, the cam cover and then re-index the cam.

I have done similar work, but not this specific work. I have a pdf created by some else that was posted here last year. If you want a copy to see what's involved let me and I can PM or email.

Good luck!

Year? :)

02 wr426

For an '02 it's a 30 minute job.

But....

The WR timing is off because of the restrictive exhaust, thus, you'll need a more freeflowing pipe if you don't already have one.

Stock WR jetting gets really funky with the YZ timing.

Wheelsup - What is your jetting setup following the cam advance?

TCMII - Could you send that pdf.

Here is what my search turned up and it looks fairly simple, thanks motoman393.

TCMII - Can you use the pdf you have with the 02 wr426?

Wheelsup - What is your jetting setup following the cam advance?

It's actually a cam retard :)

On jetting, I don't know... I haven't done it. I said 30 minutes based on the time to access, remove, and replace both cams in my '05 WR250F.

A good starting point would be to try the stock YZ jetting for your particular year (dealer can get you that information), and adjust from there.

A step more risky would be to start with the stock YZ jetting for the euro models.

Quick and easy would be to spend the bucks for the JD kit.

If this is done, what will one benefit from doing it? More like a YZ I guess....

If this is done, what will one benefit from doing it? More like a YZ I guess....

Bingo. More like exactly like a (heavy) YZ.

The difference between the YZ and the WR, as far as the engine goes, is the pipe, airbox, grey wire, and exhaust timing.

The airbox is more restrictive due to the battery taking up some of the area. Opening the right side helps, at the risk of admitting more water/mud. I woudn't mess with it for trails other than to remove the snorkel.

Bingo. More like exactly like a (heavy) YZ.

The difference between the YZ and the WR, as far as the engine goes, is the pipe, airbox, grey wire, and exhaust timing.

The airbox is more restrictive due to the battery taking up some of the area. Opening the right side helps, at the risk of admitting more water/mud. I woudn't mess with it for trails other than to remove the snorkel.

YZ/WR Airboxs are the same on 02 models. No E-Start in 02. Not sure if the YZ has the snorkel though.

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