For reference, a no.5 caliper fits a 165mm front and 145mm rear IS mount and a no.3 caliper fits a 185mm front and 165mm rear IS mount. None of the 2 piece calipers used 140/160/180 rotors, only 145/165/185. A Hope HBSM20H postmount frame/fork to IS caliper adaptor adds 20mm, therefore that...