Re: Micargi Rover 7 speed.
Hambro, you have gears...why a sprocket adapter? SHIFT THOSE GEARS MAN! Get yourself a shift kit if you're going 2-smoke, then put a tuned pipe on there as well. Might as well get the most out of your bike.
Micargi's are great bikes. I've had Firmstrong, Schwinn, XYZ, and the Micargi rides the best of all of them.