Cassette: a group of stacked sprockets or gears around the rear wheel of the bicycle with a rear derailleur. There is usually between five to 12 gears in again over a cassette. Rim brakes use pads that grip the wheel rims, whilst disc brakes use rotors and calipers to deliver https://bike-engine-oil93826.blogdun.com/35655619/the-single-best-strategy-to-use-for-engine-bike-electric