FORMER East-German firm MZ isn't a company that most would immediately associate with technical innovation. Sure, the firm's Walter Kaaden-developed two-strokes of the 50s and 60s were the forerunners to all strokers since then, but to most MZ is intrinsically linked to cheap smokers from the tail end of the Soviet era.
Although easy to miss, the firm actually showed something fairly remarkable at last week's Intermot show in Cologne. The 125 SF prototype featured a single-cylinder four stroke with no conventional throttle, instead relying on variable valve lift and duration to control the amount of mixture entering the cylinder. With no butterfly or slide getting in the way in the inlet tract, where they inevitably cause complex turbulence at anything less than full throttle, the motor's efficiency and emissions are immensely improved. So called pumping losses, when the engine is wasting power by struggling to suck air past a part-closed throttle, are also significantly reduced.
The idea itself isn't entirely new. BMW has offered its own take on the idea – Valvetronic – in many car engines over the last decade.
Of course, MZ's recent history has seen the firm bouncing from one crisis to another. Having closed down entirely in 2008, it was bought by a consortium including ex-GP riders Ralf Waldmann and Martin Wimmer, with funding from Malaysia. The firm has stuck with scooters, mainly electric ones, since then, although a return to 'real' motorcycle manufacturing has always been part of the plan.
The company's experience with electric scooters could also be set to lead to an electric enduro bike, with the firm showing a concept at Intermot. The E-GS is a 105kg electric off-roader with a 30-45 minute range. Similar in concept to machines like KTM's electric off-roader, such a bike could help open up new off-road riding facilities in areas where conventionally-fuelled crossers would be too noisy.
