With gas prices as high as they are, it's making more and more sense to start riding to work and for short trips to the store. But I'm not exactly light. Using a Horsepower calculator it divined that I would need 5-6 horsepower to keep me around 45 mph. Obviously it doesn't bother me to actually pedal, the motor is just so it won't take me over two hours to get to work. So I want to make sure that pedal assisted motorized bikes work out ok. And I was wondering if you can have changeable gear ratios for hills, or speed, etc.