High compression

[stewart]

that would vary some with port timing and  ring seal   but 230 or so

[doordie]

Are you guys calculating with the piston below the exhaust port or above? Cam.

The right way in my opinion and even almost the whole "twostroke-world" is when piston close exhaustport and start begin to compress.


(Look at Kawasaki manual:Low rpm/exhaust porttimes low(KIPS)/more compression)
                                   High rpm/exhaust porttimes high(KIPS)/less compression

As always: just my 2 cent

[stewart]

doordies right  i was giving  total from 86 by 86 to my 35cc chamber

[BDI]

At some point when the pipe starts working the theoretical compression ratio will become the actual ratio. It is best to build the engine based on the theoretical ratio. If you build the engine based on the exhaust port hight what you think is a safe compression ratio will become astronomicaly to high when the engine comes on the pipe.