I'm somewhat familiar with Gates PolyFlex belts, as I own a Dolmar/Wacker metal cut-saw which uses the 7 mm Gates Polyflex. They handle, at least in this width, almost 7 HP from the Sachs-Dolmar 72cc engine, and I've been looking at fabricating a drive system for my little 32 cc engined powered bike with an eye towards a flexbelt. Has anyone made or used a PolyFlex belt drive in a bike drive system? Seems like the 5MM width would be perfect for a moderate power, 32 cc 2stroke engine application. I've got some parts I'm putting together for this and from my own experience with the Wacker with some pretty long days cutting big pieces of scrap steel and iron into small bits, the Polyflex belts really hold up under use. I guess it surprises me that there are no articles in the forum about home builders using these belts instead of cog-belts or chains. For one thing they're more tolerant of tension and can handle a tiny amount of misalignment. This will be driving a fairly large diameter friction drum for the rear wheel, I'm trying to keep the rear drive for this bike as low tech as possible without resorting to an side hung friction drive with a tiny drive diameter.