Flat Mount fixture
This adapter provides correct caliper mount positions for both frames and forks. The Incepi fixture is the only flatmount fixture that supports the full range of rotor sizes on both frames and forks, based entirely on official Shimano geometry.
This Flat Mount jig can be used to attach Flat Mount caliper mounts to any bicycle frame or fork. The fixture requires a 3/4"(0.750") dummy axle. A 20mm dummy axle option is available upon request. The design geometry is for 140mm or 160mm rotors. The fixture has 140mm written on it because 140mm is the base location for all Shimano or SRAM Flat Mount calipers. If you are building for either 140mm or 160mm rotors this is the correct fixture.
The fixture uses a small mounting block for frames. A simple plate attachment is available for forks. The frame block has two pairs of raised features which lock into the caliper mounting slots, keeping them parallel and preventing rotation during welding or brazing. The features are 34mm apart, and in the correct position relative to the axle as per bicycle industry standards. Any standard Flat Mount caliper mounts may be used. They may be purchased from Paragon Machine Works, other suppliers, or made by the framebuilder. The fixture is sold with the frame block as standard. The fork plate may be purchased separately.