Bottom bracket height?
The Bottom Bracket height (above or below the weel base line) defines the feel of the bike. The modern and long geometries tend to have a high bottom bracket (varying from +15 up to +60mm on some frames). That gives more clearance for obstacles, but makes it more difficult to pull bunny-hops types of moves. You just get used to relying more on pedal-power techniques. Once you balance on the rear wheel, the bikes feels the same, but you have a higher reach for sidehops (because your whole center of gravity is higher).
