> Mark Kinsler Wrote:
> Please be careful. Your craftsmanship is unquestioned, but that thing
> does not look at all like a conventional motorcycle. A motorcycle meant
> for high speed travel looks like a motorcycle for good reasons: the
> steering geometry, the center of gravity, the suspension, the tires, the
> wheels, and the brakes are meant for that kind of service, for roads are
> not always kind.
> I suffered some serious injuries on a motorized Schwinn bike last
> October when I hit a poorly-maintained manhole cover and went sailing
> over the handlebars. Broke a collarbone and my neck, but I've recovered
> completely. The helmet--a silly bicycle helmet--saved my wretched life;
> half of it was scraped away on the pavement.
> I've since purchased a real moped--1984 Trac Clipper, weird to work on
> but built like a tank--and I wear a real motorcycle helmet thereupon.
> Mark Kinsler
Thanks for the heads up and you are correct! Normally a bicycle becomes unsafe around the 35mph mark. I have done the whole department store bike with a motor thing and have broken pretty much everything possible on them - rims, spokes, hubs, frames, chains, etc. Over time you learn what works and what doesn't, and after replacing so many broken bicycle parts over the years I don't even use bicycle parts on most of my builds anymore - either custom, moped, or motorcycle. I actually have a big bore Briggs 4stroke on a stretched beach cruiser that is significantly faster than this bike as well. I know how to calculate rake and trail for proper steering geometry, I install hydraulic steering dampers to prevent tank slappers at high speeds on any bike I make that does over ~45mph, and know where and how to reinforce key spots on the frame to hold up to the increased abuse. Still not saying its "safe" and I wouldn't recommend others to try it, but I'm not just throwing motors on stock bicycle frames and hoping for the best :). This frame has been reinforced and modified where necessary, has proper rake, adjustable steering damper, DOT tires rated to 62mph, strong #41 industrial chain with perfect laser aligned sprockets, all parts properly lubed and serviced, new head tube bearings, brakes cleaned and adjusted, etc. Center of gravity is low thanks to the low and centered motor, and weight distribution is pretty close to 50:50. It feels very planted and stable at speed. Since you never know though, I also wear my full face motorcycle helmet when riding - even if I am just staying in the neighborhood.
Still wouldn't call 60mph on anything home made 100% safe, but I do take more precautions than most :). If the stock sealed bearing Tomos wheels are an issue though, I can replace them...I assumed they would be OK if balanced with good tubes and tires @ 65ish since I couldn't find any examples of them failing, but like I said its my first moped build and I am always open to learning! Wouldn't be hard for me to lace up some custom 17" wheels with 10ga spokes and get some additional tire OD at the time time to make up for the gearing limits lol. Could upgrade to disk brakes while I am at it!