SRAM Rival 1x to 2x

I’m on Rival 1 with a 40t chainring and an 11-42 cassette. If I were to get a compact double crankset with something like a 10-34 cassette (or maybe bigger than 34) would I need a new rear derailleur?

I believe so, as the 1x mech is quite a different design to cope with the normal 10-42 cassette.

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Are you just wanting more range and don’t necessarily need more gears?

If so I use a Ratio Long Cage & an 11-51 Shimano cassette – it works beautifully. (I don’t care about big gaps between gears, I understand that others do!)

Are you just wanting more range and don’t necessarily need more gears?

Context is a possible road riding trip to the Alps. Having been doing a little bit more research though I reckon if I went Rival 2x I’d end up with more gears at the low end but lose the lowest gear I’ve got now. Because according to SRAM their 11-36 and 11-42 cassettes are not compatible with 2x.

So if I had an 11-32 cassette with a 50/34 crankset I’d be worse off in terms of lowest gear.

Or am I missing something?

I have a Rival DUB chainset on my new gravel bike with 43/30 chainrings and a 10-36 cassette. It is 12 speed. The 30-36 lower gear is a nice bail out option on steep gradients.

I went 2x with rival and kept same 42t cassette and derailleur, but switched to 50/34 chainset. Worked albeit not the best shifting I think too big a range for setup to cope with.

have since gone back to 1x but converted shifter with ratio mod and running 12sp eagle cassette and derailleur now.

I went 2x with rival and kept same 42t cassette and derailleur, but switched to 50/34 chainset. Worked albeit not the best shifting I think too big a range for setup to cope with.

Yeah, I think SRAM say the 42t cassette is 1x only.

My concern for the Alps isn’t that I wouldn’t have a low enough bottom gear available on 1x, it’s more that the limitations of the gaps at that end of the cassette might become more obvious on very long but not necessarily super steep climbs than they are on my usual riding.

I’ve Force 1 which came with a 42F and 11-42R, now running 44F and 11-46R.

Works great.

Hope chainring and Shimano SLX cassette – existing SRAM Force 1 shifter and rear mech.