i just bought a mountain bike with the offroading tires....is it a good idea to ride it on the streets? am i compromising much in terms of stability, etc? in the rain?
also, i'll be driving cross country in a convertible Trans Am with a bike rack in the back carrying this bike. what kind of effect would this have on mileage? it's a V8 and every bit helps so i might not take the bike if it's going to drop my MPG by 2 or more.
If you're riding on streets, slicker tyres are a great idea from a speed/efficiency perspective, as well as a stability one. You'll go noticeably quicker, and have much better/more confident cornering abilty.
I'm not sure about how the towbar-fit bike racks affect mileage, but I do know the roof ones do increase wind resistance quite a bit. Obviously with a convertible, though, that won't be an issue 😉
I'd suggest doing a google search or something and see if anyone has written any sort of web site about it.