I figgured out why my yz timing sucked

I started researching the yz timing and found you can count the number of pins between the cams the see if you got the timing correct. Well I took of the top of the engine and counted 14. That means I retarded the wr timing 1 degree instead of advancing. No wonder it had NO low end. Ran fine though... :applause: I am taking it up north to to a trail this weekend, I hope it is alot better.


all I can say is.... hang on.

Where up north?

What do you mean "count the number of pins"?

He means counting the number of cam chain rivets between the exhaust cam wheel punch mark and the intake one. 13 is WR timing, 12 is YZ timing.

This is very interesting... we had a thread a couple of months ago where the TTer was telling his WR400 had 14 pins and was running fine... I almost did not believe him.

I'll try to find this thread back again...

Okay, here is a little more information. valves needed adjusting so I did that at the same time I changed (or attempted to) to yz timing. I must have went one tooth counter clockwise by mistake. Also I didn't know about counting the pins at first (which would have been much easier). So I got it back togeather and it started and ran fine. The idle was a little messed up, but took it up north and did a 60 some mile trail ride. The power sucked, had no low end at all, it felt like I was riding an old xr250. couldn't tape the throttle to get the front up to save my life. Got it home, did research here and found you could count the pins. Counted and I had 14. Played around with it a bit and got frustrated and went in for the night. The next day counted again I had 15... :applause: Somehow I must have jumped another tooth while trying to figure it out. So I set it to 12. Tightend everything up and started turning over the engine with a wrench and it was hitting the piston and wouldn't turn all the way over. So I re timed from scratch counted 12 pins, got it back togeather and it is runing good. I am taking it up north tonight to do a trail ride and I hope the power will be back and better than original.


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