Zipp super 9 clincher disc road rear wheelthe super 9 is the definitive all round wheel originally intended for time trials track racing and tour de france style events it has quickly become a favourite among ironman and long distance athletes it is also the stiffest disc wheel that zipp make features hub model 188 disc hubbrake track width 26 73mmnominal tyre bed width 21 5mmaxle quick releaserim carbon discmax tyre pressure 125psi 862barsdimpled surface yestrack adaptable yesweig