As if motorcycles weren't impressive enough already, now they're starting to shed the terribly un-hip (by modern standards) internal combustion engines that have traditionally powered them in favor of something more environmentally friendly. In their place you will find sleek, noiseless electric motors that offer the same or better performance than their gasoline-powered counterparts.The newest entry in the field is the Mavizen TTX02, a race bike which will be available next year. As we reported previously, the design limitations inherent to building motorcycles make for an especially appealing engineering challenge, so as these technologies mature, we can expect the innovations to trickle up the mobility food chain to cars, buses, trucks, trains, and hopefully more.