28.6 could be correct for 725 but it takes a 27.2mm post? makes me think the band on would be 31.8mm
Unless the tube isn't cylindrical, steel tubes which take 27.2 seat posts use 28.6 FD clamps. Can't think of a single exception off the top of my head, although it was theoretically possible to build Ishiwata 017F (French sizing) to take a 27.2 post despite the 28.0 OD :-)
Unless the tube isn't cylindrical, steel tubes which take 27.2 seat posts use 28.6 FD clamps. Can't think of a single exception off the top of my head, although it was theoretically possible to build Ishiwata 017F (French sizing) to take a 27.2 post despite the 28.0 OD :-)