Chainwheel compatibility with Shimano Alfine (single ring) The chainring on my Shimano Alfine 39T crankset (FC-S501) is severely worn and needs to be replaced. Can I replace it with any chain ring that has the same BCD, bolt count and teeth? I am looking in particular at replacing it with a chainwheel from the 105 range (Y1M339000). Will it fit? I am concerned mostly about the shape of the tabs not meshing properly with the spider, or does it not matter? Do all Shimano chainrings have the same cutout?

Shimano's 5-bolt road chainrings don't have special tabs or spacing, so you just need to match the BCD of the cranks and chainring. You should have no trouble there as they'll both be 130 bcd.