i think you are right, except that you cant always be at the right rpm, because you would be going too fast, or too slow. if you are out in the desert, or riding along on forest service roads, you have a wide speed range that is acceptable for those conditions, and big tires and tall gears dont matter so much. but when you encounter hills, or rocks you cant maintain that speed and when you shift, you will be out of the sweet spot. it can be done, and lots of people do it. for slower stuff, you can drive in low range alot and just shift through the gears...ie 5th gear in low range for speeds under 45 (or whatever it happens to be).

light tires rob less hp and that helps compensate for the bad gearing....

try it and see how it goes...worst comes to worst, you buy big tires and end up shelling out more loot for gears, or you just sell the tires and go back to 32s <img src="/forums/images/graemlins/cheers.gif" alt="" />