Riding Rich
New Member
It's easy to see the size difference in the top ends of these motors.
Allthough the overall size externally is close.
The Jug / Head And Piston of the PK80 are much bigger.
Also notice how the Combustion Chamber of the 48cc and the 68.5cc is allmost the same size.
Puzzling i'll tell ya. Guess this Slant Head is Higher compression.
And i believe if you set the head so it fires towards the exhaust it will run cooler.
Anyway here's some pics.

Allthough the overall size externally is close.
The Jug / Head And Piston of the PK80 are much bigger.
Also notice how the Combustion Chamber of the 48cc and the 68.5cc is allmost the same size.
Puzzling i'll tell ya. Guess this Slant Head is Higher compression.
And i believe if you set the head so it fires towards the exhaust it will run cooler.
Anyway here's some pics.
