Josef Cadek設計的可折疊自行車

Major goal of the new design is to offer full-valuable bike with great ability to be folded, stored in small spaces (cases, car trunks etc..). Main feature of the design is the circular frame. It allows unusual folding. Both wheels have overhung mounting. After releasing safety lock nuts wheels can be turned around relevant axis into the frame. Because of folding of the rear wheel momentum transfer from crankset to rear wheel must be Pisible. Common chain system is replaced by belt system with outer toothing. Belt is mounted on two rollers. Both "chainwheel" and pinion have outer toothing as well. It altogether ensures right direction of turning and Pisibility of the whole system.
In the rear hub there is internally geared hub, analog to Shimano Nexus system. Shifting is of the GripShift kind. Saddle can be folded by pressing down red safety lock, it releases saddle support to be turned back towards the frame. For folding the handlebars cyclist must first release revolving safety lock nut on the top of the head set. Then the handlebars can be moved back towards the frame. Bike is equipped with disc brake in the front and the clamshell brake at the back. Thus brakes don't block folding of the wheels. This kind of bike will be welcomed by people in the "over-trafficed" cities, young people, students at the campuses. It can be use to good effect in large industrial facilities, airports, cities centers as a rent-bike. Another usage is "parasitic" means of transport. User can leave her/his car at the parking outside of the city center and then continue riding bike loaded in the trunk. Term "park and ride" will have a new meaning. Colouring works as a safety feature.