harley davidson, Revolution engine

Manufactured starting in 2001. The Revolution engine is currently used on only one Harley production model -- the VSRC. The Revolution engine is different. This engine is water-cooled rather than air-cooled and its V angle is 60 degrees rather than 45. It has four overhead cams rather than two cams in the crankcase and is fuel injected. This engine is smaller -- only 69 cubic inches (1,130 cc). It has a much shorter stroke, allowing it to rev to 9,000 RPM and it produces 115 horsepower.

There is also other kind of engines that harley used to have like the knucklehead engine, panhead engine and the flathead engine and etc.

Since 2001, the revolution engine came out they have since been using this design on this model (as far as i know) and as from what i understand is much better compared to the older designs.