Bike touring bike type women wheel size 28 inch model 2017 series specialized vita frame material aluminium frame geometry trapeze bike frame sizes cm 36 40 44 cm frame sizes s xs colour black braking system disc brake brakes tektro brake disc diameter frontrear 160160 rear derailleur shimano altus number of gears 24 gear system with derailleur front derailleur shimano tourney brake type hydraulic disc brake cassette shimano rear