as an enterprising consumer might expect, there's one other place you can read about this new groupset ;-)

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Dan Empfield
aka Slowman

Dan, do you know if the new AXS groups can be configured to work with an 11 speed cassette? I hope so given the electronic nature of the group (no cable pull differentials to contend with).

I could be wrong but I assume I can't replace my freehub on my Aerocoach disc (ridden on a 2012 Speed Concept 7.8) with an appropriate 12 speed freehub?

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

Wait, can you not get a 53x39?

"The spec and options are pretty much the same as with RED: 12 speed cassette; 10-tooth 1st position cog, and 3 chain ring size options, each with a 13-tooth differential (50x37; 48x35; 46x33)."

A friend of mine bought it and realised afterward that no, you can't, and that given the current offer if you don't want disc brake you have very litle choice for the wheels you can use. For now I beleive Zipp's are the only disc wheels you can use ? Rear hubs available are Zipps and Chris king only I think.

That is very disappointing! Seems like it wouldn't have been a difficult thing to implement either...

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

Because no one needs a 53 tooth chain ring and everyone needs a 10 tooth cog.

Chainring changeable quarq ftw!

As my understanding, there is no option for 50x37 in the new Force group, per the SRAM website and the latest GCN video on the groupset

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the world's still turning? >>>>>>> the world's still turning

As with the MTB community, XD was an open license from SRAM that would allow ANY hub manufacture to develop XD to fit their specific system. I believe that it cost them nothing to do this. This link will take you to all current manufactures that have an XD or XDR option. https://www.xddriverbody.com/ Hope this helps... the only hold out was Shimano (from my understanding). I'll let you guess as to why :)

you're right. the only problem is if you have an inventory of wheels that predate the current methodology that all (except shimano) now use: replaceable end caps for QR or thru axle; and replaceable drivers.

no. 11sp. that would defeat the whole purpose of the groupkit.

there is no need for any chain ring larger than 50t. if you think you need more than a 50x10, i'm happy to do that math for you.

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Dan Empfield
aka Slowman

i don't remember that on the lowdown i got on this group. but i'll check and report.

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Dan Empfield
aka Slowman

Weird, Chris King isn't on that list, but they sell hubs with XDR?

I don't think that it would defeat the whole purpose. In my case I'd like 2x11 wireless shifting with the smaller blip box and the AXS software. If they were to release an update/re-packaging to their 11s groupsets then I would agree with you.

Edit:
Unless of course we are taking the cynical (truthful?) view that they want to only sell full new groupsets and not allow upgrading parts of the kit.

---

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

Great call...thinking that it's just a matter of SRAM updating the site. Have to believe there are a handful of manufactures that have an XD or XDR option, and not on that list/site.

Is the pricing for this based in reality or is this another "trickle that shit up" moment?

the new AXS system is organic in its approach. there is not, to my knowledge, any 11t 1st position 12sp cogset for a 2x system. correct me if i'm wrong. i think eagle is pretty much it and i don't think you want a 50t inner cog on your 2x system. that leaves you with 12sp cogsets that have a 10t 1st position cog (if it's SRAM).

so, with SRAM AXS, the derailleurs, shifters, chain, all optimized and available only for 12sp, what 12sp cogset with an 11t 1st position cog did you plan to put on this groupset?

if you're saying that SRAM should just have made this all available starting with 11 speeds, then it needs to accommodate you by tooling up for a whole new set of cogsets and chain ring sets. or, if it eschewed the 10t altogether, you'd have the whole crowd of folks who'd complain about SRAM's lack of the obvious choice: a 10t cog.

what SRAM did was make a choice based on breadth. if you just to the gear inch math, starting with 10t (a cog you'll need, but so sparingly you won't have worn out in 10 years of everyday riding) what you'll see is that this approach makes the most sense. the problem is that some folks have wheels from a half-dozen years ago, or older, that won't be cross-compatible. yes. that's a problem you and i face from time to time.

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Dan Empfield
aka Slowman

did you read my article on this? apparently not.

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Dan Empfield
aka Slowman

I've done that math.

• Mechanical Advantage:


• 50/10 = 5 (higher top end)
• 53/11 = 4.818
• Delta Mechanical Advantage (assuming a SRAM 12sp 10-33 cassette):


• Using a 53t (mean of 0.336), going from...


• 13 to 12 is 0.34
• 12 to 11 is 0.401
• 11 to 10 is 0.482
• 15 to 14 is 0.253 (for reference)
• 33 to 28 is 0.287 (for reference)
• Using a 50t (mean of 0.317), going from...


• 13 to 12 is 0.321
• 12 to 11 is 0.378
• 11 to 10 is 0.455
• 15 to 14 is 0.238 (for reference)
• 33 to 28 is 0.271 (for reference)

This tells us a few things:

• With either chainring, the jump from 12 to 11 is a relatively large change in feel. From 11 to 10 is even more drastic.
• The use of a 50t rather than a 53t brings brings the jump from 12 to 11 into a more "normal" feeling range. 11 to 10 is still big, but should feel like less of a jump than with the 53t.
• In either case, per the reference lines, anyone telling you that gaps at the high end of the sprocket are too big is full of it. You need the gaps that big for it to feel like a more "normal" progression between sprockets.

MSRP for SRAM Force eTAP AXS = $1250 - $2000 per their website.

Is this actually cheaper than Sram Red eTap?

RED eTap is about $1,000 more than Force eTap. that makes Force eTap AXS about a quarter to a third less costly than RED eTap. while the least expensive RED eTap complete road bikes i could find were about $7,500 (canyon) and most were $10,000 or north of that, apparently the bikes will start out in the $4000s, complete, with this groupset. but i haven't seen yet what those complete bikes are, or how they're otherwise spec'd.

again, some of this is on the front page article!

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Dan Empfield
aka Slowman

Don't use that. Take the ratio between the gears. i.e. 14->15 is a ~7% gear reduction, 10->11 is a 10% gear reduction.

What you're calling "delta mechanical advantage" doesn't scale well for comparisons. It makes a given rear gear jump look bigger if you're in a bigger chainring, and it inflates the magnitude of jumps in the high part of the range compared with jumps in the lower part of the range. So a 46/10->46/11 jump is .418 and a 33/28->33/33 jump is .179, but your legs will feel the latter as a massively wider step, because it's an 18% reduction whereas the former is a 10% reduction.

Similarly, for plotting gear progression, you should use the log of the gear ratios so that jumps of the same ratio have the same size on the chart.

You didn't list the MSRP of Red, or any prices for force. But you have a vague statement that this will be cheaper than the former. Apparently you thought that was sufficient.

you're right. only the 2 smaller chain ring configs are offed in Force. so, 48x35 and 46x33.

i did a little calcing. a 48x10 is 126 gear inches, same as a 53x11. so, that's what you get with a 48x35 and a 10-whatever in force etap.

that said, force cranks use the same 8-bolt pattern as do RED cranks. RED chainrings are all direct mount. so, you could buy either the direct mount RED 50x37 w or w/o the integrated Quarq PM, and it'll bolt directly onto the force crank.

me? i wouldn't do that. if i ever need a gear bigger than 126" i'm probably already pooping my pants.

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Dan Empfield
aka Slowman

You have nearly zero info about the pricing about this groupset aside from that one sentence about mid-$4k bikes spec'd with it.

I went directly to the SRAM web page to pull the pricing info; would help if you quoted their estimates directly in your article since price will be a main driving factor for those interested.

Right now, amazon sells sram red eTap for $1400, at least that's what it seems to me. If this group could come in at $1000-1200 (the low end of the sram webpage estimate), that would be nice.

2500 euro from Bike24 LINK

i gave you what i knew, and a third less than your usual SRAM, with complete bikes $3000 less, seems to me to have answered whether this was "'trickle that shit up' moment". i took "trickle that shit up" to mean a supposed downstreamed product that didn't really grant a meaningful savings over the halo product. please accept my apology if "trickle that shit up" means something else.

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Dan Empfield
aka Slowman

This may have been talked about elsewhere, but I have three questions:
(1) will the old blip box work with this system (i.e., RD) or are we forced to but the new blip box if we want 12 speed?
(2) what do we have for 12 speed wheel choices right now and/or will 11 speed wheels be adaptable to 12 speed?
(3) can you shift directly from the new blip box like the old blip box or must you use clics/blips?

SRAM's commitment to the 10T cog included throwing away the current standard chainring sizes. There's no 53T chainring option, but 48-10 is roughly the same ratio as 53-11.

The name "standard" double for 53-39 is a historical artifact. 52-42 also had a long reign before gradually morphing into 53-39, and today 53-39 has become much less popular than 50-34 and 52-36. It would have been baffling if SRAM had kept 53-39 around for AXS while also not including the modern "compact" doubles.

here's more on pricing. here are aftermarket MSRPs, bearing in mind that SRAM has a min and a max. what i have with force is just one price. i'm comparing this to RED's min pricing:

2x Hydraulic Road Disc Brake: RED: $3,648: Force: $2,678. it's about 26.5 percent less if you use RED's min MSRP pricing.

2x Rim Brake $3,488 RED: Force: $2,478. here it's around 30 percent less, 29 percent less if you use the min pricing, around 30 or 31 if you use the max pricing.

these are w/o power meters. i don't know what happens to the prices when you add power meters. i know what happens to the RED prices, but not the force prices. yet.

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Dan Empfield
aka Slowman

What's the math on the extra friction the 10T causes too?

What if you're a pro and riding huge chainrings like many do? I've seen 54s, 55s, even 56. Will it still work?

i would guess the old blip box works, but i can't swear to it. i'll find out.

your old 11sp wheels will work if they accept one of SRAM's drivers. for years zipp made its wheels with its XD driver, and for years all wheel companies save shimano made their hubs so that an XD driver could be put on there.

these AXS groupsets require an XDR driver. same thing. the wheel companies knew about this for many months, and they pretty much all should have an XDR driver they make that fits onto their wheels. if you have an older wheel, as long as it was XD driver compatible, it's XDR driver compatible, and can be used with these AXS groupsets, i.e., they'll take an AXS cassette.

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Dan Empfield
aka Slowman

Red AXS offers a 50-37 chainring combo. The 50-10 ratio is equal to 55-11.

Thanks. I edited to add a third question while you were typing a response

(3) can you shift directly from the new blip box like the old blip box or must you attach/use clics/blips?

also, RED's 50x37 will bolt onto a Force eTap crank. Force relies mostly on a 4-bolt spider system. Force chain rings => spider => crank. but, you can bypass all of that and direct mount to the crank, if you have direct mount CRs, which is what all RED CRs are.

i just don't even want to know how much money a set of RED CRs are in the aftermarket, tho.

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Dan Empfield
aka Slowman

as i understand it, the new blip box works exactly like the old, it's just smaller. but i don't understand the question. i've never shifted directly from the blip box. i don't know how or why you'd do that. or that the old blip box allowed for that. can you give me a use case or an explanation?

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Dan Empfield
aka Slowman

Sure; I’ve gone to wireless shifting. No clics. No blips. I attached my blip box to my extensions and shift only directly from the blip box (click on + and - buttons to shift up and down). Saves me a few hundreds bucks and don’t have to deal with hiding or dangling wires. With 1x set up, it’s quite easy. I’m wondering if you can do the same from the new AXS shifter.

well heck. okay. learn something new every day. i'll find out.

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Dan Empfield
aka Slowman

Looking here at the Euro retailers all I see is an option down to 170mm cranks. Is that correct? If so hard pass.

did you see my response to lightheir? with prices? i did some more nosing around and also generated some 1x comparisons:

1x hydraulic groupsets. Force eTap AXS sells in the aftermarket for $2,328 compared to RED's $3,178, a 27 percent discount. The biggest discount i could find, RED to force, is on 1x rim brake, where Force is about 32 percent less than RED, $2000 to $3,000.

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Dan Empfield
aka Slowman

turdburgler wrote:

Looking here at the Euro retailers all I see is an option down to 170mm cranks. Is that correct? If so hard pass.

we had this very discussion about RED. they've heard a fair bit on this topic, and i asked about this when interviewing the fellow in charge of all of this, ron ritzler. so that you don't have to read it all:

"Will you make RED cranks with Quarq PMs in lengths shorter than 170mm?"

"Yeah, I saw that question [on this very forum]. In talking to our aftermarket team, who makes those decisions, we’ve heard those requests, and will add more lengths, in RED, aftermarket, down to 165mm."

they read these threads. they read what you write. they make decisions based on what you write. and believe me, before Force eTap AXS was ever launched they knew they'd need to make some addn product, as i think you can see.

my guess: 165mm cranks; 10-42 1x eagle cassettes (now that eagle + eTap = great 1x gravel options); and a 43x30 chain ring option or, failing that, a longer cage RD paired with a 10x36 or so cassette. i doubt these guys are settling in for a long design and manufacturing vacation.

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Dan Empfield
aka Slowman

Availability is end of April, at least that's what my LBS told me when I called to order it.

Thanks.

Dear SRAM people,
I like you a lot. My cross bike has a SRAM 1x setup. Get your heads out of your butts and make shorter cranks! :)

Sent with love.

hey. one thing. about shorter cranks. and, look, you heard it hear first, and you might've heard it from me first. at least as regards tri.

the value of shorter cranks is to open up your hip angle without sacrificing aerodynamics. so... for those of you who demand 165 cranks, you're demanding a crank that grants you a head start on the downstroke but with less torque generated. this benefits you if, and only if, your aero position is at that very point of being too low, i.e., if your hip angle at TDC is very close to being too acute.

is that you? and i don't mean you, turdburgler, i mean all youse out there. the short crank thing is a solution to the tight hip angle thing. if i see your position, and your pads are up in the air, and you're asking for 165 cranks, and you're taller than 5'6", then i'm asking, why?

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Dan Empfield
aka Slowman

How can I be an offended and triggered internet user if you keep taking away my reasons to be angry with your “facts”?!

I think there might be some confusing of Red eTap AXS vs red eTap. I think his point is that Force AXS is quite a bit more expensive than the older Red eTap despite being significantly cheaper than Red eTap AXS.

i don't recall any RED eTap bikes every selling, complete, for less than about $7,000. Force eTap AXS bikes will sell for $2k to $3k less than that. usually eTap bikes were more money than dura ace di2 bikes.

mostly, you guys aren't going to buy this group aftermarket. mostly it'll be OE. what will overwhelmingly impact you is what the OE prices of this group will be and how that will be expressed in the prices of the bikes you buy. if you're able to buy AXS electronically shifted tri bikes for $4,000 or even anything under $5,000, that's a slice of the market SRAM was shut out of, new eTap or old. shimano barely played in that price range.

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Dan Empfield
aka Slowman

~180 cm here and my stack is insanely high. After a fit at CycloLogic, I got custom 13cm risers made for my Shiv TT. I like running 165's as it helps keep my quads out of my lower ribs (the bottom couple flare out), but my body is very odd when it comes to this so I already know that I'm an outlier that SRAM won't worry about.

The new Force AXS cranksets are offered in 165mm, 167.5mm, 170mm, 172.5mm, 175mm, 177.5mm. It's right there on the SRAM website.

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the world's still turning? >>>>>>> the world's still turning

But I want a 163.65 crank

see callin's comment. i think i'll hire him to cover this stuff from now on.

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Dan Empfield
aka Slowman

These spec options might be what you'll see on OEM bikes that hit the retail floor that have been spec'd with Force AXS. SRAM will usually list all their options, both OEM and AM (aftermarket) on the site, but that necessarily doesn't mean it's available for AM purchase. A good example of this is their RockShox line. Most AM forks are only offered in the RCT3 damper. The RC option you will see 80-90% of the time on spec'd bikes. Price is the name of the game in that world and it allows OEM's to have a good, better, best spec option for consumers and retailers. But maybe I'm wrong about this too. Just adding context as to maybe why...

So can someone explain why we need 12sp or why we need a 10 cog instead of adding an extra cog to reduce the gaps between the existing ones? I'd rather have better chain line.

Also... you don't need to have a 400W FTP to have a reason to use a 54 or 55 chain ring. Those that use 54 or 55s don't do it because so they can go 40mph on flats.

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What's your CdA?

Where is the 10-40/10-42 cassette option for 1x?!?! is the R. Der even compatible with that size?

I don't want an eagle r. derailer or 10-50 cassette for road/gravel

29-35 MPH on flats?

One thing that isn't clear to me is the clearance of the FD for larger tires. I currently can't fit anything larger than 700x38 on the "old" etap, and I've read they have addressed this with AXS using a slimmer FD design. So, is this a slimmer battery or FD to get more clearance with AXS. Is the AXS battery the same as the old one? I know they are compatible between the old and new etap, based on reading about the battery, but what I can't gleam is if the size and shape of the battery is the same. Got any info on this Dan? thanks!

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_______________________________________________

55x11@100rpm = 39.1mph

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What's your CdA?

We need 12 speed for the same reason we needed 11 when 10 was the norm, why we needed 10 when 9 was the norm, etc.




Sigh, it's a "chicken or egg?" situation. You need a 10T cog because you have smaller chainwheels. Or you don't need big chainwheels because you have a 10T cog. Pick your reason.

And even though you have to choose a smaller rear cog to get the same cruising gear ratio because of the smaller chainwheel, your chainline isn't all that different from where it was with 11-speed because the 10T cog is where the 11T cog was before, the 11T cog roughly where the 12T was before, the 12T roughly where the 13T was before, etc, etc, etc. If you "cruised" in a 54/16 before, you'll be in a 50/15 now and the difference in lateral chain deflection will be no more than 1/2 the cog pitch.

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"They're made of latex, not nitroglycerin"

1. 12sp: i asked why we needed 6, when 6sp came out. i stopped asking after 10sp.
2. 10t: range. it's a math exercise.
3. the width of the cassette is basically the same. so, chain line is unaffected.

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Dan Empfield
aka Slowman

Oh, most TTers with the big rings don't use the 11 for the bulk of the TT. The big ring is so they can use a more efficient cog.

If you have another use-case for very large rings other than flattish TT, track pursuit, or track sprinting, let us know!

You could do that with the old system. Nick at TriRig came up with the very slick setup pictured below. I mocked it up for myself and it indeed works well especially if you put a bit of skateboard tape over one of the buttons.

i believe i have both FDs here, old and new. let me check, and do some measuring.

now, on that subject, part of the problem is frame design. i'm riding exactly what you are: 700x38mm. and on old eTap. my chain stays are 425mm. i don't see eye to eye with every bike maker on this, but, here's my approach to gravel geometry:

1. start with road geometry.
2. figure out every way that a 38mm tire on a 700c wheel impacts something, and normalize for it.
3. ask yourself what you now need to change.

in other words, the larger wheel radius (353mm instead of 336mm or so?) impacts trail. shoe overlap. it raises the bike, so, you've got to correspondingly lower the BB from the wheelbase line from, say, 70mm to 85mm. you add chainstay because the operative metric becomes the leading edge of the inflated tire behind the seat post. you also change the bike's design to account for clearance in the Y and Z axes (front axle to the fork crown, the width of the fork blades, the width of the chain stays.

now, as a frame designer, you ask yourself if all that comports with the use case. no, you might say, you want a higher BB. okay. i don't, but i respect that you might. maybe you don't want road geometry, road contact points. okay. why? let's arm wrestle it out.

the point is, if you did what i suggest you do, as a bike maker, and eTap FD batteries don't hit the leading edge of an inflated road bike tire in 25mm, there's no reason why they should hit a gravel tire.

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Dan Empfield
aka Slowman

SRAM is claiming that the new chain is equivalent in efficiency to 11-speed chains. So if that's the case the old Friction Facts data should still be pretty valid. We're talking about the order of a full Watt vs 11T @300W. Possibly more. And 11T to 14T is another 1.5-2W. 14T appears be about the cog where efficiency gains pretty much disappear. So the jump from 14T to 10T is around 3W. I think that's fine for most purposes.

But a specialist in track or TT would want to use at least a 14T cog, then pick a ring that gets the ratio they want with that cog.

I'm not a big short-crank advocate (tried them for a couple years and switched back), but you aren't actually giving up anything definitive. Or probably gaining anything either! Aero and power were both a wash for me. It's what "feels" better. In my case I seemed to prefer the greater range of motion with longer cranks, even though the hip angle is pretty tight.

My thought here, given that the new Force AXS cassette is a pinned variant and not a fully CNC variant like RED, it should be something that they could pull together if demand is there. SRAM is usually really good about creating these down the road. I could see this being something they release at Sea Otter or some other gravel event like BWR. Fingers crossed...

What is skateboard tape and why do you need it? I’m still playing around with either (1) Nick’s setup using the bottom half of a sram shifter; or (2) just attaching the blip box to a Garmin mount which is then attached to my extensions with those oval rings m. Initial impressions were that the second option was more comfortable for shifting .

From the Bike Rumor first ride review:

"I do think that for it to be a true contender for a gravel group lower gearing may be desired, but SRAM is coyly hinting at more mix and match 'Beyond Road' options later this summer."

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"They're made of latex, not nitroglycerin"

I think I read on Glory Cycles that AXS will only work with AXS so old blip boxes would not work with the AXS RD, but now I can't find the Q&A. Maybe you can confirm.

Let me ask about chainlines and other compatibility issues as this is now way beyond my knowledge. Are we able to use any old crankset and/or chainring with a 12 speed AXS set up (which we could with 11 speed)? For example, I have FSA Gossamer Crank with a Power2Max PM and Rotor Chainring designed for 1x use. Is there any reason those parts wouldn't be compatible if I wanted to use them with a 12 speed AXS RD, cassette and new blip box?

This really depends on your intended use of the bike. In my case, the bike is custom. I wanted road geo that fits fat tires - my geo consideration are a little more complicated than that, but that’s really the starting point that drove my design.

Now, to me, that bike has short chainstays - 415mm, low bb drop - 78mm, steepish HTA - 72.5, stack a bit higher than my road fit, and reach a tad shorter than my road fit, but reach is created around the use of a 90mm stem (instead of my typical 110mm I use on the road).

This produces a very capable fat tire road bike that utilizes 650x42-48 and 700x35-40, depending on the terrain I plan to ride. For my larger tire tires to fit I had a custom wire harness built so I can mount the FD etap battery in another location. It would be nice to not have to do that!

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_______________________________________________

Basically sandpaper with adhesive on the other side. Makes it easier to distinguish between the buttons.

I checked. No can shift w/new blip box. Getting rid of that feature helped them make it smaller.

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Dan Empfield
aka Slowman

Exactly... that was my point as the ST article said that no one needs anything larger than 53x11.
I would have preferred they kept the classic ring sizes 55/54/53/52/50 and instead of adding an extra 10 cog they could have filled gaps in the high/mid range. This just seems like changing stuff for the sake of changing stuff.

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What's your CdA?

Any word on backward compatibility?

I'm baffled (as was James Huang in his cyclingtips review) why SRAM didn't release something to fill the gap between the 10-33 and the 10-50 cassettes. I really thought AXS Force was going to yield a 10-37 or 10-39 to pair with their 48t 1x front ring.

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wovebike.com | Wove on instagram

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.

If sunrace comes out with a 12s cassette compatible with an 8-9-10 HG cassette body, then I'd be very interested. I still love my tri-spokes, no desire to swap those out anytime soon, but they aren't XD compatible.

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Swimming Workout of the Day:

Favourite Swim Sets:

2020 National Masters Champion - M50-54 - 50m Butterfly

well, no. because there's eagle AXS. so, that means AXS must be compatible with eagle cranks. but i really didn't spend any time educating myself on AXS for offroad. my only eagle interest is in pairing it with the road crank and shifters.

but this does bring up one point: if the eagle chain is required to go with the eagle cassette, and the flat top chain is required to go with the road AXS groups, but the mullet calls for the road crank, that means the eagle chain must be compatible with the road crank, even tho the road chain isn't compatible with the eagle cassette. i'll need to run that down.

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Dan Empfield
aka Slowman

Ok lemme clarify, AXS is definitely not compatible with non-Sram cranks?

exactly. it's the chain rings. i'm working on another theme, another article, right now on "autofeed", and it's a problem brought on, insidiously, by the very efforts we all make to reduce friction in the drivetrain. one way to reduce friction is to have precise keyway relationships between chain and tooth.

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Dan Empfield
aka Slowman

this is exactly what i'm looking for... they currently missed a sale due to not bringing that range; and it seems like quite a few others looking for it as well

Hi Dan

This is what I want to do - upgrade to the new Sram AXS 1x TT but keep my existing Quarq crankset with a 1x chaining. Given that a number of third party 1x MTB chaining manufacturers (Wolftooth, etc) advertise their chainrings as being 1 x 10/11/12sp compatible, those chainrings are presumably compatible with the Sram Eagle 12sp chains (and others).

Therefore, if the Road AXS chainrings are compatible with the new 12sp Eagle chain, and the Eagle chain is compatible with third-party 1x chainrings, one presumably could use any 1x chainring with the Eagle chain (probably also the flat-top?).

Obvioulsy, SRAM is not telling anyone their chains will work with other 1x chainrings as they want you to buy their new crankset / chainrings too if you upgrade to AXS...

Am I missing something here?

https://sram.zendesk.com/...AM-Eagle-drivetrain-

so i guess that's not intended/possible

Thanks, I also found too this which seems to answer the question.
https://sram.zendesk.com/...etrain-gearing-setup-

SRAM RED eTap AXS™ chains are only compatible with SRAM RED eTap AXS™ chainrings. Eagle™ chains are designed only for 1x drivetrains with a 10-50 or 11-50 Eagle™ cassette (note: SRAM RED eTap AXS™ 12-speed chains are designed only to be used with RED eTap AXS™ 12-speed XDR cassettes).

Guess I'll have to buy that sexy AXS 1x aero chainring too...

Restricting the usage to only Sram cranks is a non starter for anyone with a different crank power meter, for example my type s power2max. Does Sram have no plans to release 110 BCD rings?

i don't know if i'll answer your question with this post, but:

1. for any of your questions, you're asking them on the right day. i'll be seeing a lot of manufacturers today.

2. one good thing with SRAM, if your product is late-model enough to have an 8-bolt attachment between the SRAM crank and whatever you want to put on it - 4-bolt spider, direct mount chain ring, etc., is that this carries over onto AXS.

3. i'm severely, acutely, undercoffeed as i write this. my functional threshold IQ is 70 right now. just, if there's a 110bcd spider with that 8-bolt pattern, you can put on whatever chain ring you want. if your crank w/Quarq PM has an 8-bolt pattern, you can put on whatever chain ring you want. SRAM is fully attached that that 8-bolt system. so, if you pull off your drive side crank arm and look at the back of it, and there's 8 bolts in a circle attaching whatever you have attached to that crank, you're gold.

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Dan Empfield
aka Slowman

Thanks Dan, appreciate your taking the time to respond.

I'm still on a 3-bolt Sram/Quarq so out of luck there. From some further digging around on the net, I think I have it worked out (it's quite complicated, I needed plenty of coffee myself!):

• The Road AXS chain has larger rollers than the Eagle chain.
• The Road AXS chainrings are designed to engage the larger rollers of the Road AXS chain.
• But, because the Eagle chain has smaller rollers, it will still fit on the Road AXS chainrings (thus why you can use the Eagle chain in a mullet configuration with AXS chainrings)
• However, this will not work the other way. Ie. because the Road AXS chain as larger rollers, it is will likely not fit on other (non Road AXS) 1x chainrings that can accept Eagle chains and are designed around smaller rollers. The Road AXS chain *might fit these chain rings, but probably not "optimally" so there may well be wear and chain retention issues if the chain does not "sit" in the teeth fully.
• In all cases, you must match cassette and chain - Eagle with Eagle, Road AXS with Road AXS.

What I haven't quite worked out is why, technically if one can use an Eagle chain on Road AXS chainrings, you can't also use an Eagle chain with the Road AXS cassette. Sram only says:

"Can I use a SRAM Eagle™ 12-speed chain on an SRAM RED® XG-1290 cassette?
No. Eagle™ chains are only compatible with Eagle™ cassettes."

Rotor released their 12sp which fits on existing hubs: https://rotorbike.com/...__from_store=spanish

11-36, 11-39, 11-46, 11-52

The aftermarket will make AXS cassettes. Just give it more than 2 seconds. It was just released.

But the RD is only capable to 33t, so we also need a new RD.

Shimano says RD-RX805-GS is only good to a 34t cog but I'm using it with an 11-40 cassette just fine and it definitely looks like it would work with an 11-42. Might be different with SRAM but usually you can make things work. It just might not be officially approved.

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-Mike

Vertex Fit Systems (http://www.vertexfitsystems.com) | Bikeworks (http://www.bikeworksma.com) | Russo Racing (http://www.r2tri.com)

I think this move makes business sense for SRAM. Campagnolo and Shimano already had their own standards. When SRAM started, they didn't make full groupsets,so they had to piggyback on one of the existing standards to sell their products. Once they did make their own full groupset, they didn't have the following to get customers to commit to a unique standard, so they soldiered on with Shimano's. Now they are big enough to have their own, so why let customers buy Shimano products for their groupsets? The transition will cause some pain for customers (and by extension SRAM's revenues), but once people make their choice, it's the same as the Shimano/Campy situation, no?

Or you can add a RoadLink

thats a janky set up IMO and decreases the shift accuracy.... defeating the point of a $400 derailleur

Can't have everything, I suppose

If the force AXS uses the same parrallelogram design as the other Sram clutched RD's, then it will work exactly like as if Sram spec'd it with a larger rear capacity since the cage essentially only moves horizontally and relies on B-screw being turned in to rotate the RD far enough way to clear the largest cog.

No X-horizon geometry on the Red or Force AXS eTAP. That's only for 1X-specific RDs. These new RD's aren't "clutched" so much as "damped"

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"They're made of latex, not nitroglycerin"

Ah, got it.

Hello XX29er and All,

https://www.velonews.com/...x-drivetrains_493185




The 2X drivetrain had lower frictional losses in every gear than the 1X system—with the caveat that the chainrings matched up with the ideal cogs in the rear.

The average friction within the 1X drivetrain was 12.24 watts. This was computed as the sum of the drivetrain power losses in each of the 11 gears divided by 11. The average friction of the 2X drivetrain was 9.45 watts, computed as the sum of the power losses in each of the 15 optimal gears divided by 15.

This is just under a three-watt average difference between the two drivetrains.

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Cheers, Neal

+1 mph Faster

Interesting read. According to the justification of their results though, it would seem that the margin would go down significantly with a larger front chainring. Testing a 48 is useful for XC and road but most tri guys running 1x won't have anything smaller than a 52. And most aren't running a 10 tooth small cog yet as well.

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Benjamin Deal - Professional - Instagram - TriRig - Lodi Cyclery
Deals on Wheels - Results, schedule, videos, sponsors

And still SRAM is trying to force a small chainring with a 10 tooth cog (◔_◔)

Seems like they have gone out of their way to vary as many factors as possible.

Ugh, could they have introduced any more variables into that to muddy the results? Why didn't they test Force 1 against Force 22? Not that I would expect the outcome to be substantially different, but in a test that's trying to quantify small differences in efficiency between 1x and 2x, you'd think they'd want to isolate the changes to only those required for 1x. Run the same chain. Change the cassette ratio, but get it from the same family. And choose two RD's from the same manufacturer, at least.

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"They're made of latex, not nitroglycerin"

Aside from the variables, "average" losses aren't exactly the best measure for everyone since in most cases we spend a majority of our time in the middle cogs. Still the difference seems to be 1.5-2W. My conclusion would be that it is a net gain after 3-4W aero gains.

Still an insightful test, thanks for sharing. Better to have this data point than none since they can't reasonably test every combination of group sets, chainlines, and chainring sizes.

The chain compatibility is very awkward.
Could I use an Eagle chain with Force etap in conjunction with an ultegra chainset?
Or would the Eagle chain still be incompatible with the Force etap cassette?

I have a Stages power meter crank and therefore want to keep the shimano chainset.