Excellent post Larry. The vibration is still there and will remain as long
as Harley stays with their patented 45 degree V-twin. That angle is the only
reason the Japanese bikes will never be able to copy the Harley sound. Now
S&S Company in Viola Wisconsin builds some monster Harley motors in the
120-130 horsepower range and if you used the Harley or aftermarket
transmission you have a built in reduction drive as well as a way to lower
RPM at cruise. Harley's haven't leaked oil since the Shovelhead went out of
production but have been known to blow a cylinder base gasket which will
cause the engine to leak but replacing the stock gasket with a performance
aluminum one properly coated with sealer will solve that problem real quick.
The newer 88 inch double overhead cam models might offer more in the way of
torque but even that is an easy fix with any Harley engine buy changing the
camshaft. Both Andrews and Crane offer a full selection of shafts to suit
any particular situation. Seems that low end torque at lower rpm's would be
ideal for aircraft applications.
Doug Rupert
