Get started on your mountain bike journey. The BIG.NINE 40 uses our latest aluminium frame to give a tough but lightweight base for high-value, high-performance kit. With updated geometry and a 120 mm air-sprung fork, it's a confident off-road machine that packs in versatility for everyday use, while Shimano's CUES 1x9-speed drivetrain and the hydraulic disc brakes are simple but effective.