metal, chain, sprocket, gear, bicycle, bike, machine, part, sport, equipment, steel, technology, drive, gearwheel, component, transport, wheel, iron, metallic, object, alloy, gearing, chainring, cog, cycle, ring, gearshift, cycling, pinion, cogwheel, mechanical, group, race, mtb, teeth, transmission, speed, transportation, macro, circle, chrome, tooth, vehicle, mountain, rear, rack, cassette, stainless, riding