I would buy one if it were compatible with 11sp.. but the cost of change my bike to sram force etap is higher that buy a new bike with ultegra di2, since my wheels (and most wheels) are not compatible with 12sp, and my Tacx Neo 2, also not.

What I'm saying is quite the opposite of the section in italics. From the way I understand this (and I may well be wrong, or a minority) we have the following options:

SRAM Red ETAP (1x11, 2x11)
SRAM Red ETAP AXS (1x12 2x12)
SRAM Force ETAP AXS (1x12 2x12)

Given all of the above are actuated electronically then with the new benefits axs provides (customising of set up, smaller blip box, battery monitoring etc) it seems like one of the options within the AXS app could easily have been 'cassette size' allowing for 10, 11, 12 speed cassettes to be used. Just because someone can afford to update their groupset doesn't mean (and shouldn't) require a full wheel feet swap etc.

In short, the benefit of these new groupsets is not solely 12 speed

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Practise doesn't make perfect, practice makes permanent. Only perfect practice makes perfect!

Someone please help me out here. I’ve read this thread, and the front page article. I searched the interwebs. This website https://www.xddriverbody.com wasn’t clear. How do I determine if my wheels (HED Jet 6) and smart trainer (Wahoo Kickr Gen1) are compatable with the SRAM 12-speed cassette? Guidance to determine any wheel/trainer compatibility is ideal, as I suspect others have the same question. I haven’t been able to find a clear answer, and the added cost of new wheels/trainer/modifications are a consideration for deciding between Ultegra Di2 or Force ETAP.

if your HED jet 6 can accept an XD driver, it can accept an XDR driver. HED will tell you. but i'd guess yes.

smart trainers, same thing, if they take an XD driver, they'll take an XDR driver. but that's a little more complex. trainer makers weren't as quick to adopt driver body changeout functionality. i don't know if the gen1 kickr accepts an XD driver.

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Dan Empfield
aka Slowman

From what I can gather from Hed (but far from clear), you need the new HU206 hub body: https://store.hedcycling.com/hed-hub-bodies-50-100/
It seems to be the 12sp XDr hub for Jet series.

Not sure about Wahoo but I'd assume they will release and XDR hub for their trainers soon, if not done so already. Have you tried contacting their support?

i'm not sure i understand. you're saying that SRAM should have allowed you to buy a full AXS group, minus the cassette, and let you reprogram this group backward to 10sp? so that you could use your inventory of 10sp cassettes?

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Dan Empfield
aka Slowman

Yep!

Having checked with Aerocoach I cannot get an XDR driver for the wheel set I use, and SRAM Force ETAP AXS is effectively the same price (in the UK) as SRAM Red ETAP (non-AXS).

If I am spending the same amount of money I'd rather have the newer kit (and smaller blipbox)

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Practise doesn't make perfect, practice makes permanent. Only perfect practice makes perfect!

Dcrainmaker describes trainer compatibility in detail in his write up

yeah. SRAM was pretty much explicit in what they felt was their reasonable expectation for backward- and cross-compatibility, which is, to "honor" the investment in wheelsets, but not to dumb down the groupset. that means the groupset itself is going to be 12sp. period. and 10t 1st position. this is because - and this is now just my opinion - these groupsets pivot around the chain as the central player. you could almost say that they started with the chain, and built everything around that. the chain, the cogs, the chain rings, the shifter operation, spacing, all revolves around that flat top chain. anything that doesn't work with that chain won't work with AXS, with one exception.

if you want to mix/match eagle with AXS, then you use the eagle's chain. and this is where i think SRAM is very much animated by cross-compatibility. they'd rather spend their time thinking about how much of their line, going forward, can be mix/matched depending on the use case. they're much more interested in making sure all their MTB, CX, gravel, road, tri parts are compatible with each other, because of the strange use cases you and i come up with.

the one area where they are interested in backward compatibility is for your past investments in wheels. but it'll only go back so far, and that distance back is limited to hubs that accept XD drivers. it took pains to ensure that all the wheel companies has a lot of notice, and that its new driver fit on old XD driver-enabled hubs.

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Dan Empfield
aka Slowman

That all makes a lot of sense, and despite my questioning (and slightly tongue in cheek comment earlier) I don't disagree with SRAM's approach.

On an aside, thanks for taking the time to humour me...this is the most involved I've ever been on Slowtwitch despite being a lurker for most of the last half decade!

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Practise doesn't make perfect, practice makes permanent. Only perfect practice makes perfect!

well, shoot, apparently i haven't insulted you enough to run you off! ;-)

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Dan Empfield
aka Slowman

Even from 34/50 to 56/9, gear ratio progresson does not span a full decade (and intervals of a given cassette even less so), so plotting on a log scale does not have much of an impact. Plotting the log(ratio) on a log scale does make a nice nearly linear curve (until you get too close to 1:1). It still shows a difference based on chainring. It does set off the "feel" discussion, as it is concave in the opposite direction.



Looking at the actual spacing of a cassette, though, you see a linear progression toward too-close-to-tell-the-difference in the first several cogs (1-tooth differences) and a step change when it moves to 2-tooth differences, and then a definite split in behavior between ratio-ratio (left axis) and delta ratio(right axis). To me, the difference data looks like a clear attempt to keep the delta ratio near the average for the cassette. And, if you're actually moving at the correct speed for the particular ratio, I do not think it feels like a "massive" jump in gearing (except for that wacky 50-tooth cog).
The other problem with the ratio-ratio you suggest is that, you're correct, it mathematically takes the chainring size out of the equation. Moving from a 39-12 to a 39-13 should feel similar to moving from a 52-16 to a 52-17; it should not (and does not) feel anything like moving from a 56-12 to a 56-13.

the blip boxes are not interchangeable.

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Dan Empfield
aka Slowman

A 10-37 or a 10-39 would be ideal for me. I wish they would release either one.

https://www.velonews.com/...ike-stood-out_483906

I predict upwards of 10 pro tour riders on 1x by the end of this calendar year, and that's if SRAM sticks to only providing a 10-33 and 10-26. If they go up to 10-39, I predict upwards of 20 pro tour riders on 1x by the end of this calendar year.

I've been on 50 x 11-36 11s for a while now, and I can do HC climbs.... but 48x33 is a tad harder of a gear. That's not going to cut it.

A 48x39 is almost the same as 34x28

and 48x10 is close to a 53x11

So, either Sram gets its act together, or e*Thirteen makes this 12s cassette, or Shimano cleans house with a 14sp 1x road groupset: https://www.bikeradar.com/...-speed-patent-50973/

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wovebike.com | Wove on instagram

Dan can you find out when all the components will be available for purchase separately. The "mullet" configuration is what I want to install but I don't want to buy an Eagle AXS groupset + a Red/Force AXS groupset to get all the pieces. I've checked with my local dealers and I get different answers. One says April the other says July.

Thx!

Me as well.

let me see how one would obtain a mullet, esp an eagle/force.

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Dan Empfield
aka Slowman

The only thing that necessitates the XD-R driver is the 10T cog. And this system would work fine, especially in 1x configuration, without a 10T cog, just as the gravel 1x11 works fine with either the XD driver and a 10-42 cassette or the old-school HG driver and an 11-42 cassette, and 12-speed Eagle works fine with an XD driver and a 10-50 cassette or 11-50 cassette on an HG driver.

It's early, and I'm not gonna criticize SRAM for not having a HG-compatible cassette for this yet. Maybe it comes when the presumed downmarket 1x12 mechanical systems are released in the future, just as it took Apex1 and NX Eagle to usher in the HG compatible cassettes for those systems. If SRAM doesn't go there, somebody in the aftermarket will. I all but guarantee that the folks at Sunrace are already working on a SRAM 12s Road compatible cassette that will fit an HG driver.

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"They're made of latex, not nitroglycerin"

x3... 46 or 48 x 10-37/39 12s be about perfect

what appears to be the case is as follows: SRAM is limiting sales to those who're buying complete AXS groupsets. in other words, if i wanted to buy individual pieces i couldn't do so. this is because there's too many orders just for groupsets. individual pieces won't be available until later in the summer.

i take this to assume that SRAM would not accept an order for a full mullet "groupset".

the price of groupsets is simply the aggregation of the individual pieces (so i'm told). so, making a mullet wouldn't be more expensive than buying a mullet groupset. i am seeing SRAM eagle AXS, whatever that is. groupsets. but they're with trigger shifters. and i doubt they're with road cranks, that is, cranks that give you a 145mm or 150mm q factor.

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Dan Empfield
aka Slowman

Interesting. Some websites already have individual parts listed for sale (RD is the only one I can’t find). I wonder if that will change or if individual stores will just buy groupsets and break them up on their own...????

The ever-growing increase in speeds is so “8-minute abs”

https://m.youtube.com/watch?v=JB2di69FmhE

yeah, i rooted around. but i could only come up with chains. and one or two other things. and with a mullet it's an eagle derailleur, and an eagle chain for that matter. what you need are road AXS cranks, and road shifters. and i suppose the BB for road but i doubt that's hard to come up with. RED or force AXS road crank and the shifters get you there. as long as you could get eagle 10-50 12sp cassette, chain, RD, you'd be in good shape. the rest of is, disc brake calipers, etc., not a big deal.

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Dan Empfield
aka Slowman

So you can confirm that AXS is only compatible with their Red or Force cranks.