Hybrid city bike commuter bike wheel sizes 26 28 inch series vermont jersey frame material aluminium frame alloy 6061 aluminium bike frame sizes cm 45 55 50 cm frame sizes m s l brake type v brakes brakes promax tx 115 bicycle fork suspension fork fork zoom rear derailleur shimano nexus number of gears 8 braking systems rim brakes coaster brake crankset prowheel chain kmc z610 rims x pert x3 tyres kenda k935 stems zoom aluminium h