Re: Metrakit Eureka!

• Author: j (---.dsl.chcgil.ameritech.net)
• Verified User: mopedenthusiast
• Date Posted: 05-12-08 12:44

not to rain on your parade, but i don’t understand why shaving the piston skirt would change the height the piston ascends to at top dead center. the base of the cylinder is still flush against your case, right? so the distance traveled should be the same. i don’t think you can attribute the performance increase to that mod . . .

. . . unless maybe by shaving the cylinder skirt you’ve increased the volume of the crankcase, thereby lowering the primary compression ratio, and that’s had a positive effect on top speed? jennings claims that there’s an optimal primary compression ratio, and that a lot of people should actually lower theirs for best results.