Moped Army

Hmmmm I better join your forum so I can know about all these things. I run a 12mm Bing, which was standard here. never shortened my piston (wouldn't know how, unless it was replaced with a shorther one), but mine will do a pretty good 40mph on the level. I only weigh 137 pounds though. About all I did that brought me more power was polish the ports. After I did that, I had to jet up a little, and I got almost 10mph more out of it. It doesn't 'foru-stroke" at all anymore, and it used to constantly, before I polished the ports.

I'd like to see a 15mm set-up someday.