i am stinking, the calipers are the same, just that th e red ones mount to th e front, the black ones to the rear
-ie they are a similar casting, but the bore 36/44 is a different way up - plus the spring clip hinge to the bottom
-hense ones red ones black, so as not to confuze
and they made a pad surface smaller so as not to overhang the 305 discs
-for the smaller wheels?
-???????????????
-no, ?