Sport touring motorcycle sportbikes were redefined (for marketing purposes) as sport touring bikes: the 2000 Kawasaki ZX-6R sportbike became the 2004 ZZR600 with just a change to a fairing bracket. Sport touring motorcycle A sport touring motorcycle (sometime a "sports-tourer") is a type of motorcycle that combines the performance of a sport bike with the long-distance capabilities and comfort of a touring motorcycle. The first sport-tourer is said to be the fully faired 1977 BMW R100RS. Journalist Peter Egan defines the sport-tourer as a "café racer that doesn't hurt your wrists and a touring bike that doesn't feel like a tank," and identified
Ducted propeller reducing pressure. This lowers thrust and torque of the propeller. At the same time, a circulation occurs, resulting in an inward aimed force, that has a forward component. The duct therefore has a positive thrust. This is normally larger than the thrust reduction of the propeller. The small clearance between the propeller and duct reduces tip vortex, increasing efficiency. As drag increases with increasing speed, eventually this will become larger than the added thrust. Vessels that normally operate above this speed are therefore normally not fitted with ducts. When towing, tugboats sail with low speed and heavily loaded propellers, and