I'll be interested to know how you get along in the Hollywood area with a gas bike. I recall getting a ticket down there on the boulevard on a Friday night back in the '80's for not having a license plate light on my rebuilt Fiat spider 850 convertible.
Your electrics sound cool, but maybe you should use more modern and lighter bikes.
Here's a build I'm working on. I got this Scwinn Traveller bike for $5 from a junk dealer last summer, switched alloy rims for the steel ones it had, and now fitting a small 49cc slant with a custom ground 34 sprocket, and a chrome tank and chrome extended muffler that should be extra quiet.
It's going to have a single speed freewheel and I may be using a narrow chain and sprocket on the motor if I can fit them- everything is being considered to keep the weight minimal, and I wouldn't chance building on a lighter frame myself. Projected final weight about 37 pounds or so- and with the narrow wheels, it should roll pretty well.
