The Fixxer works with many Shimano brand hubs, but not all. There are some Shimano hubs we know will not work with the Fixxer. They are: all Silent Clutch, Dura Ace made before 1997 and after 2003, XTR M970/975, XTM770/775, Saint, and DXR-MX70. Additionally, Shimano has in recent years begun to use proprietary axles instead of their old standard 10x1mm standard axles. Since Shimano is constantly changing and updating designs, we simply do not always know what hubs will or will not work with the Fixxer. What we can tell you is that if you have a Shimano hub using a 10x1mm standard axle, the Fixxer will probably work. If your hub is not Shimano, or you are not sure what its insides are composed of, then you're better off getting a dedicated fixed gear hub or wheel.