crankshaft bolt on damper turning tool

[Ed Wright]

Originally Posted by randy wilson

I've just found out that on the base circle, I can be perfect in one spot, and bump it, be perfect, hit it again, and be a couple loose. I've found this on about every grind from every company to be true. I always set tight at the loosest area of the bottom. I set my valves rather tight anyway, but that's just me. Try it and see if you get the same results. Now you have me curious.

If you have zero runout on your rollers, you should not see that much on lash variation at different points on the base circle. So, where do you find the loosest/most lash point?
We used to set them at TDC, compression stoke. Had the dampener marked each 90 degrees. Follow the firing order. Two revolutions got them all.
Most everybody I know bump the starter, set the intakes when the exhaust valve starts to open. No exact point. Set the exhaust when the intake is almost closed. I check my valves each day at the races. Very seldom have to adjust one.
And, stopping at the same exact point each time would very unlikely.
Lash does not vary while checking it at different points.