Do fly/cam marks line up exactly?

Hi guys

I noted while doing the shims on my YZ426, that if I set the cam marks to align to the head, the I bar on the flywheel is some degrees away:

Cams:20120209_002.jpg

Fly:20120209_003.jpg

Click for bigger

The mark you can see on the flywheel in the top left of the flywheel cover hole, is the bottom of the I beam.. It's a few degrees out. If I rotate it to line up exactly, the cams don't rotate by even a whole tooth. The bike does run, but doesnt idle too well (valves need shimming too) just wonderd if this could have an impact

Edited by cjard

Rarely. But if you have an old worn cam chain, it can cause the misalignment to be worse than usual. Consider replacing it. Line up on true TDC and check. If the cam would be better lined up on the next tooth one way or other, move it. If not, it's OK.

If you would have it off by one tooth it would be a lot more off from each other then than.

I just did mine and it was exactly like that.

Even if you are a little off the completely top dead center there is a little bit of a dead zone up there so you can be off by a little bit and it won't do anything. A new chain and tensionner would be the cure to get that to line all up:).. Mine did anyways

yeah it would be more helpful for us if you took a picture of the cams with the timing mark lined up perfectly so we can see how far off they are. I was having a hell of a time with my bike shortly after I got it. it's really easy to adjust if that's what needs done but if you're is that close then the only thing that would probably fix it is a new chain.

Rarely. But if you have an old worn cam chain, it can cause the misalignment to be worse than usual. Consider replacing it. Line up on true TDC and check. If the cam would be better lined up on the next tooth one way or other, move it. If not, it's OK.

hes right, i just had the same problem on an rmz 450, replaced the cam chain and then they lined up mint.

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