bigtrucker2007
New Member
I and looking to modify my 66cc HT motor. I was hoping someone could help me on how to do some port mods and what are good upgrades. thanks
Do not make the intake ports mirror smooth, a "brushed" finish will actually run better.
The little bit of surface irregularity helps create turbulence which aids in atomizing the fuel in the intake charge. The exhaust port and cylinder head both could benefit from a mirror polish.
When working on the cylinder, be careful to only cut the ports when drawing the file or sand paper away from the bore. If you cut while going towards the bore you risk flaking the Nikasil plating off around the port edges.
Even after doing all this work, you will not notice a tremendous improvement, but there will be one none the less. Notching the piston about 1/4 inch on the intake side and just cleaning up the ports a little bit seems to do more.