In our experience this is the least expensive bike that you should buy to ride for true mountain biking, as oppressed to riding bike paths. The MB2 is equipped with the Microshift Acolyte 1 x 9 speed single chainring drivetrain. Every good mountain bike today has a 1x drivetrain. Some bikes at this price point still have 2 chainring cranksets and front derailleurs. These are improvement over triples, which have always worked poorly, but really why have them? Moving from 2 or 3 chainring drivetrains to 1x eliminates the single worst working part on any mountain bike, the front derailleur. The wheel size varies with the size of the bike. The smallest sizes have 26 inch and 27.5 inch wheelsets and the medium and large have 29 inch wheelsets. The MB.2 also is equipped with tubeless sealant ready wheels and hydraulic disc brakes. This is a solid, reliable and affordable trail capable mountain bike. Matte Black available in store, Bright Yellow is available to order. Comparable Bikes Price Drivetrain Disc Brakes Cannondale Trail 3 $649 Microshift Mechanical Giant Talon 4 $650 Microshift Mechanical Batch MB.2 $699 Microshift Hydraulic Specialized Rockhopper $749 Shimano Altus Hydraulic Trek Marlin 5 Gen 3 $849 Shimano CUES Hydraulic Specifications: Frame: 6061 Aluminum Fork: SR Suntour MCT 30 Shifters: microSHIFT Acolyte 1x9 Derailleur: microSHIFT Acolyte Crankset: Samox 32T Cassette: microSHIFT, 9-speed, 11-46 Brakes: Tektro Hydraulic Disc Wheelset: Tubeless Ready Double Wall Tires: 26, 27.5 and 29 by 2.4 inches wide