The Proterra Light i27 is a light alloy trail bike. The 27 mm inner rim width provides the optimum profile for tyres in the 2.3 - 2.5 inch width range. The rim profile with optimised walls provides the perfect combination of stiffness and durability.no expense was spared on the hubs, which are fitted with top EZO bearings and the rear hub is fitted with a 6-flag nut and a 5-degree bite. In short, Proterra wheels deliver the look, sound and feel you expect from high-end kits. USAGE: Cross-Country / Trail Wheel Diameter Position Spacing Spoke Holes Driver Body Rotor Mount Inner Rim Width Rim ERD* Weight** Max Rider Weight Part Number 29" Front 15x110mm 32-hole n/a 6-bolt 27mm 606 892g 265lbs W045-0218 29" Rear 12x148mm 32-hole SRAM XDR 6-bolt 27mm 606 1038g 265lbs W045-0222 29" Rear 12x148mm 32-hole Shimano Microspline 6-bolt 27mm 606 1038g 265lbs W045-0223