Checking Valve Clearence

I am trying to check my valve clearance and have a few questions/problems

1. When the TDC mark on the rotor is correct the punch marks on the camshafts are not, is this normal? possible? Which do you use if they both don't line up.

2. How do I know when I am on my compression stroke?

3. Any other help here?

Read the manual on how to do the valve clearance its really well laid out. Your 180 degrees off if your cam marks arent correct. You may want to find somebody to show you how to do this the first time. Good luck!

I had the same problems with the cam dots on my 450 when I was putting my YZ cam in. The dots on mine are below the top surface of the cylinder head, not like it shows on the diagram in the manual. I also overlooked a paragraph in the manual that states that you'll be at TDC on the correct stroke when you can get your feeler guage in to check the clearance. I guess I've just been lucky when checking my clearances, and have always been on the correct stroke cause I never ran into this problem until my "180 degrees off YZ cam fiasco" I just went through. The most important thing is that the "I" mark on the flywheel is lined up with the mark on the case cover.

this is a little tip i got off this thread awhile back. if you have found that only one cam has to be removed for shims, put a ziptie through each cam sprocket and secure the cam chain where it is before removing. the cam can be lifted out of the way enough to get to the buckets and put back where it was without moving the chain on the sprockets. if too much slack gets in the cam chain it can jump a tooth on the crank, so be careful.

The cam dots should be very close to 9-12 and 3 oclock while at TDC. Remember, these are 4 strokes. The crank shaft turns 2 full revolutions to complete a stroke, 720 degrees. At the correct TDC the cam lobes will point out and the dots will line up. Turn it 360 degrees from there and the intake is fine but the exhast cam lobes point to the rear and the dots are below the case.

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