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http://en.wikipedia.org/wiki/MZ_Motorra ... weiradwerkMZ manufactured a line of 125 cc four-stroke motorcycles using an engine that was designed in-house. The MZ 125 produces 15 bhp (11 kW) and nearly 10 lb·ft (14 N·m) of torque. It is a liquid-cooled, dual-overhead-cam design with four valves, high-voltage electronic ignition and an 11,000 rpm ignition cut-off. This engine was used in four models, all of which share a common frame. The frame is a tube-steel backbone with the engine as a stressed bottom member. Differences in the suspension, fascia, gearing, and equipment make the four models relatively distinct, despite the shared platform. All four bikes feature a six-speed transmission and dual disc brakes.
Quoted for the "all of which share a common frame." Of course the FunX and SX models have no mounts for passenger footpegs.