Sub-compact 2x cranksets with power (46/30 to 48/32) - Help me make an inventory of current options

I am in the market for a sub-compact 2x crankset WITH POWER for road/gravel high-mountain climbing. More and more options became available recently and I had to do some researching. I thought I’d share (could be of interest to some) and ask you if I missed some maybe other interesting options?

My personal preference is around 1:1 gear ratio or even less (assuming a 32T or 34T cassette), so was shooting for 30 to 32 inner chainring. I am limited to 24mm spindle as I run Di2 in BSA shell so 30 does not leave space for Di2 wire (but the list below is not limited to 24), so currently leaning towards the new Power2Max on Rotor ADLHU 24 46/30. Anything else?

What I am missing? Thanks. Pierre.

PS: I did exclude Absolute black 32T chainrings. Tried, weird chainline rubbing & inner ring rubbed on chain stays.

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I noticed you are mixing 11-speed and 12-speed drivetrains here. SRAM’s offerings have different “standard” gear ratios. Also, you should be able to run a SRAM 11-36 cassette on an 11-speed Shimano drive train, which IMHO has better gear ratios than Shimano’s 11-34 cassette.

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They have them for 4 bolt Shimano and 5 bolt 110 bcd. Put them on whatever crank you want. Just be sure the 30 will clear the chain stay.

Thanks! True, I did include SRAM AXS for completeness, but in my particular case, I will stick to Shimano system 11spd.

I do have a 36T cassette (SRAM), works actually great w/ my Ultegra RX rear mech and served me well (combined with a standard 34 inner chainring).

But the large jumps between gears bothers me for pace-lining on the flats (not so much on the way up), so ideally would love to have an all-around setup w/ a more reasonably spaced cassette.

This is admittedly very personal choice, some people would accommodate just fine large jumps. It actually works OK for me on my gravel 1x bike.

Pierre

Shimano’s 11-34 cassette has no 1-tooth jumps at all, so if you are pace-lining, that’s not a good choice. SRAM’s 11-36 cassette has 3 gears that are 1 tooth apart, so if you want that kind of range and want to be able to ride in a pace line, SRAM’s cassette is the better choice IMHO. If you already have a 11-36 cassette and you think the jumps are too big, then I think you should also stay clear of the 11-34 cassette and go straight to 11-32.

SRAM opts to have more cogs at the top end that are 1-tooth apart than Shimano. I have 11-32 cassettes from both Shimano and SRAM, and I vastly prefer the gearing of the SRAM cassette. It gives me 5 gears that are 1 tooth apart whereas Shimano gives me four. There is one odd, larger jump, but it is in a speed range where I don’t mind it (it is in the nether region that is neither fast/flat nor slow/climbing).

Plus, SRAM 11-speed cassettes have another awesome feature people don’t talk about: after switching chainrings, you have the exact same gear ratios in the middle section of the cassette whereas with the Shimano cassette, you get slightly different gears (starting with 50:19 = 2.63 vs. 34:13 = 2.62 till 50:20 = 1.79 vs. 34:19 = 1.79). If you have a look at the analogous Shimano cassette, you will see that the gear ratios of big vs. small chain ring are offset by almost exactly half a gear.

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You could mix and match two sram cassettes to get the gears of your choice.

Are you set on crank-based power? I’ve got the Favero Assioma Duo’s on my gravel bike and have been very happy with them. Plus, super easy to swap to my road bike or trainer bike if I need/want to.

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I have a praxis zayante 48/32 with a 4iiii power meter. Works great for my gravel purposes. I’d be mindful of chainring compatibility when it comes to the praxis 48/32 and power2max NGECO. It says on the power2max website that their power meter isn’t compatible with that set and the smallest you could fit would be a 50/34 with that power meter. 4iiii being crank arm based there’s of course no issue there.

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I am more an SPD kind of guy for both road/gravel/MTB (I used A600 single-sided for road). I did consider this awesome Assioma hack: A Wild idea for Favero Assioma pedals [MTB SPD Hack] - #226 by keto-rider.

I probably should have been more clear. I did the hack as well and it has been brilliant, including surviving some epic mud conditions at LandRun this year. Somewhere on here I posted a pic of my bike post race.

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This is somewhat relevant - are there any aftermarket chainrings i can slap on my force axs crank that are larger than the 48? Live in an extremely flat area.

@pimu Are you looking dual sided PM only?

No, other options possible like Stages or 4iiii. Gearing is important to me and I would happily sacrifice and move to single sided. Pierre.

So, you could easily buy the cheaper 2x10 or 2x11 version of the GRX crank and use a left only 105 4iiii or stages crank based PM. That’s probably the cheapest option, and the RX600 crank will give you 46/30 gearing.

The 2x10 crank will work perfectly well with an otherwise 11speed set up

An important consideration here is chainline. Some of the cranksets, in particular GRX, have a chainline that is further out than others.

True, and whilst it may be necessary to buy the corresponding GRX front mech I would recommend trying with the existing mech first as it may well work fine.

Cannondale do a sub-compact (46/30) Spidering for their SI SL/SL2 cranks which you can pair up with a Stages. Very light but BB30 (or variations of) only.

Mike

This is super cool, but it isn’t SRAM specific. The “magic” combination is: 15, 17, 19, 22, 25, 28 and Campy also does this on its Potenza 11 and Centaur 11 cassettes, as well as its 12 speed 11-32 cassette. The odd jump you’re referring to is the 19-22 (which is typically made from the big ring). Takes a bit of getting used to, but is no worse than one of those popular 1x setups! :wink:

It’s important to note that this “feature” only works with a 50/34 combo up front. Anything smaller and the numbers drift… bummer!

Side note, do you know if SRAM 11 speed cassettes can be run on the shorter Shimano 10 speed hub bodies? (like, for example, Shimano 11 speed MTB cassettes and the HG700 cassette?)

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I tried exactly that yesterday on my 25 year old commuter that I’m trying to update a little, and it didn’t work - the 11t didn’t make contact with the splines, and the lockring didn’t engage.

Should add that my freehub came with an 8 speed cassette - newer freehubs are often sold as 10/11speed, so that might work.

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Bugger!

My sleuthing reveals that the 11 speed Shimano HG freehubs are backwards compatible with 10 speed cassettes, with the use of a spacer (spacer goes on first, then the cassette).

Meanwhile the previous generation Shimano HG 10 speed freehubs are compatible with some “special” 11 speed road cassettes that have a concave 11th (biggest) cog carrier, like the HG700. They are also compatible with all Shimano 11 speed MTB cassettes (because they have the concave carrier). Unfortunately every cassette I’ve been able to find has two-tooth jumps at minimum… there’s no closely spaced “special” 11 speed cassettes that will work on the 10-speed freehubs as far as I’ve been able to find.