Se bikes big mountain 29 20 hardtail bikethe se bikes big mountain 29 20 hardtail bike sports a lightweight but durable 6061 aluminium frame a shimano 21 speed drivetrain sr suntour suspension forks weinmann rims and wtb nano tyres 29 inch wheels with weinmann double wall rims roll over obstacles with ease and help to maintain speed over rocky and rooty trails the 75mm travel sr suntour fork will smooth out the rough stuff so you can maintain control shimanos tourney 21 speed drivetrai