I have a 2014 Niner RLT Rival 22 with a 46x36 compact and 11-32 cassette. The front derailleur mount is height adjustable. I spent the first 6 years on the bike in the midwest and the gearing was great. I now live in the PNW and am looking for a better climbing ratio. AbsoluteBlack makes a 46x30 oval compact that I think would get me where I want to be. My questions are:
Will I need a new rear derailleur? I dont know how to tell if mine is a med or short cage.
Is there a way to measure if that small of a chainring (30t) will work with my front derailleur?
Is there any downsides to the above setup that anybody has experienced?
You don't need a new RD unless you are going to a significantly bigger cassette. If you have a clamp on FD, you should be able to lower it if your seat tube is symmetrical. If you have a braze on FD, calculate the difference in height between 30T and 36T rings and see if you can lower the FD by that much.
FDs are set by the big ring and have a 16ish tooth max difference, so you probably wont need to adjust it at all, or maybe up a bit to account for a 46T oval being 50ish at times.
i use an AB 46/30 on my 2x gravel bike and its great.
You'd be going from a 10 to a 14-tooth difference. Does it look like your RD has room to wrap more chain? If so you're probably ok. If not, you may need a longer cage.
I went from a 50/34 to the AB 46/30. Had to adjust the FD and take a couple of links out of the chain. Very happy with the result. Really like the ovals at low cadence.
