ORIGINAL: Luna_Rendezvous
I believe there is more compression because the cam timing is different when rotated slowly in the opposite direction, have only noticed this in 4 strokes.
Mike.
Not whole correct answered..
More compression in 4 stroke engine are due by the piston goes from TDC to BDC, therefore the engine get better cylinder filling.
The 2 stroke engine has poor cylinder filling than a 4 stroke engine due difficult to fill the cylinder by crankcase pressure..