Double chainset series shimano ultegra application racing bike chain wheel teeth 5339 5239 crank lengths 165 170 172 5 175 mm bolt size 130 mm construction shimano hollowtech ii speeds 2x10 housing widths 68 70 mm chain line 435 mm crank arm material aluminium pedal thread 916 1428 x 127 mm colours silver black weight 790 g