i know someone who owns a BMW bike with a boxer engine. Because the axis of the crankshaft is along the length of the bike, when he revs the engine at a stoplight, he feels a twisting motion along that axis. Quite wierd, according to him.
when the Viper first came out, it had separate sidepipes. They were said to sound like a UPS truck. A very fast one. When they rerouted the exhaust to the back, it sounded more sporting.
VW/Audi have some interesting engines:
- the straight-8 engines of the old racing Audis. Must have had really massive main bearings.
- the VW flat-4
- the Audi inline-5
- the VW VR6 engine
- the VW VR5 engine - this is the VR6 less one cylinder. As if the VR6 wasn't odd enough!
- and to defy all convention, they have those W-engines. Just add a few more, and it will be a radial engine (like those in old warplanes).