Robust thick-walled crank・Steel axle more robust・Steel pedal insert・Variety of models "FC-M640 bottom bracket 68/73 mm "FC-M645 bottom bracket 83 mm "Compatible with Press-Fit bottom bracket "34/36/38T・Weight: 906 g (FC-M640, 36T, with bottom bracket, without chainring protector, 170 mm) 938 g (FC-M645, 36T, with bottom bracket, without chainring protector, 170 mm)