If you look at these In cyl compression tests (cranking and running on a 2 cylinder V Twin) can anyone explain and possibles reasons why the Rt Cyl Running compression is so high?

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The right Cyl Running compression is too high because the the intake valve is closing too early.

When an intake valve closes too early, the piston moving up on the compression stroke will have more time to compress more air in the cylinder.

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Thanks for having a look. That is what I determined as well. cam timing and valve clearance is correct. It is a single cam push rod motor and I was thinking I would find a worn cam lobe, rocker etc but when I got it apart there is some wear but does not appear to be bad enough to cause this problem hence my post.

To measure where the True compression TDC is and any valve timing accurately, we should do the measuring using the ckp sensor along with the transducer in the cylinder.

I wish, 1 pickup/pulse per crankshaft revolution, welcome to carbureted motorcycles.

Just spit balling here. If my memory serves don't v twins have a seriously Un even firing pattern? I would think loosing half of that pattern would drastically effect the cranks velocity on whichever cylinder is dead.
I've never seen a relative compression from a v twin. What does a known good RC pattern look like?
When I get to my PC this one will be fun to play with.

Low vac. and higher compression. The tower seems to lean a bit.  (speaking about RT running capture)

I'm thinking like a "supercharge effect" from some extra air being scavenged threw a leaky valve.

Kinda like when only one cylinder in a car engine get all the EGR from stopped up ports.

Just food for thought.

Food for thought.

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