Double chainset single chainset series shimano xtr applications mtb xc chain wheel teeth 3424 3626 3828 crank lengths 170 175 mm bolt sizes 96 64 mm construction shimano hollowtech ii speeds 2x11 1x11 features shimano dyna sys housing widths 73 68 mm chain line 488 mm q factor 158 mm crank arm material aluminium carbon pedal thread 916 1428 x 127 mm colour black weight 619 g