Yes, a 45 degree common-crankping v-twin. A design neither originated by H-D nor used solely by them, historically. Well, that combined with poor carburetion and ignition at low rpms leading to a variety of misfires and generally uneven running, especially at idle.
Actually, while I thought the idea of patenting or trademarking or copyrighting an engine sound was ridiculous (as I would expect others who think this whole IP thing has gone too far would agree), I really could care less. The world really didn't need a bunch of crappy Japanese copies of a crappy old design, anyway.
actually its pretty fun, like a fine woman.