[Christ]

How much does your R1100 weigh? How's the aero on it? about 17 HP is all that's really needed to go 70+ comfortably in most all situations.. ask Craig Vetter.

I'm not looking to build it to "have fun", in the sense that everyone else thinks. It'll be fun enough tooling around in it just knowing that my hands built it, and how many people can say that?

I've got a GL1000 sitting in the yard, if it's old enough that I can get a title for it, I'll use it for a highway trike, then I'll have one for tooling around, and one for really "getting on it", as it were.

A boat tail would help by a few MPG, but true streamlining is necessary to really see any gains, because you bike has a very high Cd. I believe I read that there was approx 80% of the engine's power wasted just to keep the bike going 80+ MPH on some bikes. Yours probably isn't that bad, I think that was for cruisers and unfaired bikes.