Read more about Ask MO Anything: Transverse or Longitudinal V-Twin? at Motorcycle.com.Dear MOby,
Excuse the noob question, but what’s the difference between a transverse V-Twin and a longitudinal one, and what are the advantages of each?
It has to do with the orientation of the crankshaft. Any engine, be it a V-Twin, V-Four, or inline-Four, is considered to be “transverse” if its crankshaft lies perpendicular to the motorcycle’s wheels, i.e. across the frame, parallel to the axles. Most motorcycles have transversely mounted cranks, including all Harley-Davidson V-Twins, nearly all four-cylinder sportbikes like the Yamaha R1, Kawasaki ZX-10R, Aprilia RSV4, all Ducati V-Twins and V-Fours… including the Monster 797 pictured on the left, above.
Chain or belt drive to the bike’s rear wheel is simplest and lightest with this layout, and having the crankshaft spinning in the same plane as the rear wheel means power can be transferred through the gearbox and straight on into the drive chain and rear sprocket without making any power-sucking changes of direction.