Cassette: a group of stacked sprockets or gears to the rear wheel of the bicycle with a rear derailleur. There may be between five to 12 gears in back over a cassette. Most engines have a gearbox with up to 6 or maybe seven ratios. Reverse equipment is sometimes identified https://pitbikeengines71108.azzablog.com/35172266/fascination-about-bike-part-yamaha