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  1. D

    Port Durations for Reed Valved Engine?

    What are ideal durations for a reed valved engine (windowed piston), I'll be running a 14mm carb, expansion chamber exhaust. Should I add a boost port as well?
  2. D

    50cc Ported Cylinder?

    Hi, Just wondering if there is anywhere I can get a 50cc cylinder that has been ported. Anywhere that has decent shipping to Australia or somewhere in Melbourne that can do it (As I'm not confident in doing it myself). Thanks.
  3. jaguar

    Porting the engine

    These engines come with inadequate port durations for the exhaust and intake port. They limit both power and RPM. The transfer durations are OK. I recommend raising the exhaust port for at least a 150 degree duration for the 48cc and to at least 165 degrees for the 66cc. Go to this page to read...