Vision NS Track Crankset 1x 49T Chainring 172.5mm Arm Length 144BCD 386EVO Spindle – BLKVision NS Track Crankset 49T 172. 5mm 144BCD 386EVO N11. The Vision NS Track Crankset is purpose built for velodrome performance offering stiffness and simplicity for fixed gear racing. Its single ring configuration and robust carbon arms deliver direct power transfer ideal for sprinting and high torque efforts. Designed for track specific drivetrains this crankset supports riders who prioritize speed rigidity and clean mechanical efficiency.