Ключевые слова: abstract, action, activity, aluminum, automobile, background, bicycle, bicycling, bike, biking, car, cassette, chain, circle, cog, crankset, cycle, derailleur, detail, downhill, engine, equipment, exercise, extreme, gear, gearing, gearwheel, isolated, machine, mechanic, mechanism, metal, motor, mountain, part, repair, repairing, riding, set, speed, spoke, sport, sports, sprocket, store, technology, teeth, tool, transport, wheel,