BB30-24 for Rotor 24mm cranks CROSS - $239.99 ROAD - $239.99 $239.99 Add to Cart Fits a Rotor 24mm road crank to a 68mm wide BB Shell or a Rotor 24mm MTB crank to a 73mm wide BB Shell. Choose road bearings for road bikes, cross bearings for mountain bikes and cyclocross. Also for road bikes if you frequently ride on wet roads. This product is sold out.