I am new to MTB, been riding road for a while. I was curious about seat height and bike fit. My understanding that your MTB should be a little bit smaller then your road bike. I ride a 59CM road bike and have a 20" MTB. I usually adjust my seat on my MTB so that my legs are extended properly like I do when I ride my road bike. I am beginning to think my seat may be too high as I feel a bit uncomfortable in my shoulders and arms because they are carrying more of my weight then my arse. What would be the effects of lowering my seat? Would my pedal stroke lose some power? Would me legs/knees be under some different strains?