Dr. D flywheel weight

I am rebuilding top end on 03 yz450 the piston needs to be @ top dead center for cam installation the stock flywheel has a mark for alignment there are no marks on my Dr. D weighted flywheel HELP!:ride: can I just use a plastic straw in spark plug hole to get TDC thanks, Craig

can I just use a plastic straw in spark plug hole to get TDC thanks, Craig

Yes. You'll notice there's a sweep of 3-4 degrees of crank rotation where the piston doesn't move much at all. Use a sharpie to mark TDC on the flywheel in the middle of that range.

thanks ,I will let you know how it works out. I was worried because if im off 1 tooth there would be problems Is there a way to double check after cam installation ? should I spin crank a few times to see if marks on cam and my new mark on flywheel weight are still on, Craig

Edited by crcraig

While you're setting the cams, keep all the slack on the back side run of chain.

When you think you have it, install the tensioner, turn the engine forward to TDC and check the cam alignment. Don't turn it over without the tensioner.

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