Not so sure that's true, Ceuls. The way I figure it, the reason Harley V-Twins in particular make more torque is because they are an "undersquare" design(the stoke dimensions is larger, or longer actually, than the bore dimensions)
A long stroke motor will make more torque, but is limited by that longer stroke to lesser RPM figures, where the horsepower lives.
The modern Hinckley Bonnies are all oversquare in design(bore dimension larger than the stroke dims), which is why their redline is two thousand RPMs higher than most air-cooled Harleys, and why their powerband peaks higher. Not to mention that an OHC design(ours are DOHC, BTW) will also allow for a higher redline, in most cases.
And one more thing, because a parallel-twin's width plays a part in deciding how big it can be, not to mention the more inherent primary imbalance that(especially) a 360 degree crank parallel twin has(without a counter-balancer installed), that too has an effect upon how large of a displacement a P-Twin can be.
Older Meriden Triumph 650s were all slightly undersquare, which for their size made them quite "torquey" motors.
Last edited by Dwight; 08/09/2007 7:59 PM.
