I have an Acera 3x9 mega9 setup (FC M391) on a 2015 Fuji flatbar. I am refurbing it for secondary use, trying to replace as little as possible.
My first question is if any 104bcd 9-speed chain ring will work? Existing is an SG-X U48. The triple config is 48-36-26. The 48 has the most wear.
Second is, since I am going to a new BB, chain & cassette, is a new crank a smarter bet? Rings seem pricey compared to older NOS.
I really have no reason to swap RD & FD, or shifters, by that time it will cost like a silk purse, but still be a bit of a sow.
Thanks for any comments.