Gravel bike type mens geometry sloping comfort frame sizes l s m bike frame sizes cm 46 48 52 54 56 58 cm colour orange model 2017 frame material steel frame characteristics butted fork kona fork material crmo gear system with derailleur number of gears 22 rear derailleur sram rival gear shift brake lever sram rival crankset raceface aeffect front chain wheel teeth 36 cassette sram xg1150 rear chain wheel teeth 10 42 chain sra