see http://www.dieselbike.net/mz/mz.htm (lotsa variations)I had a friend bought one of the MuZ Diesel engine bikes.400cc single.It had a horizontal pipe along the lhs of the engine.He said it was painfully slow,with a suicidal pullaway from stationary.He said that you'd see a gap,say on a roundabout,and then hope it would still be there 30 seconds later,'cos that's how slow the pullaway was.