Cubic displacement is not really an accurate indicator of how much power an engine is capable of delivering. A perfect example of this is the 750cc Magna that was discontinued after 2003. The bike is light, which is a factor; however, the Magna 750 has the most powerful 750cc engine I have ever seen in a cruiser. The bike itself is somewhere in the size and weight range close to a Shadow 750, etc., but the V-twin Shadow cannot compete with a 750 Magna with 4 cylinders and 4 carburetors. In terms of power and speed, there is no comparison. As a matter of fact, the VTX 1300 I had was not even in competition with the 750 Magna one of my son's buddies rides. It is one little hoss of a bike with close to sport bike performance.