And I guess pressure for a mk2 cam would be less?
The only thing i am missing from calculating dynamic ratios is standard con rod length .....Tim,
Yes, less pressure because the intake is closing later. This is why the Mk2 is usually used with high compression pistons. Of course, starting a bike with the lower cylinder pressure of the Mk2 may contribute to starting problems, particularly if your rings or valves are a little soft.
David
or lower a CP a bit they have a very strong (thick) top deckSO.. using a calculator it looks like a big bore 8:1 piston on MK2 cam will give me a dynamic CR lower than a 7.5 on a Mk1 and it would need an 8.5:1 to be a little higher.
and at 8:1 the crank pressure dynamic is 136 lbs almost the same as a standard comet on 7:5
Very interesting.... especially to my right leg
now who makes a 90 bore lowish compression piston or is it back to Venolia?