The World's biggest running motorcycle built by Clemens F. Leonhardt (Germany) is the Gunbus 410 Cubic Inch V-Twin Motorcycle.The fuel injected, 45 degree 6728 cc / 410 cubic inch V-Twin runs through a 3 speed transmission. Some more like glass wheel motorbike and the enclosed motorbike. Interested folks can check it out. More including an enclosed motorbike, and glass wheels here .....
http://www.planetbt.com/motorbiking/2012/creativebikes/creative_motorbikes.htm
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BT