What is going on with Sram AXS?

I do like the idea of having a wider range of gears, however it is not worth the weight trade off for me. Where are you getting that the weight is at the center of rotation vs the edge though? Just slightly less weight from bolts on the chainrings?

Also not sure what you mean by more/less leverage, I should be able to get that by just using a shorter crank arm unless you mean something else or I am not reading it correctly.

Ultimately I do like what they are doing with having a 13 speed group but the trade off of not being able to easily change out you chainrings depending on where you are riding is a bit much for me along with having to send it back when you need new ones. I am disappointed in this release as I was hoping for it to basically be old etap with 13 speeds and a weight decrease.

EDIT: I am challenged, 12 speed it is.

It’s only 12 speed.

Mike

Just eyeballing the crank/power meter design and reflecting of many prior discussions over the years on weight differences of wheels and where the weight was located (e.g. hub vs rim).

Comparison of gear ratios between between Shimano and SRAM:

If, for example, you compare Shimano Durace compact CR (50/34) with an 11:30 cassette to SRAM’s 48/35 with 10:33, the mechanical advantage of the SRAM over the Durace is 4.80 to 4.55 or 5.6% more leverage at the upper end. Similarly, at the low end, it’s 1.13 (Durace) vs 1.06 (SRAM) or 6.9% (more efficient spinning).

btw: I do get your comments about the limitations of the design - always tradeoffs for both the product designers and the users . . . similar to what the TrainerRoad software developers go through :slight_smile:

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The Di2 weights don’t include the battery, wires, or junction box. The SRAM groups include the batteries.

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XX1 Eagle AXS looks great, albeit pricey, just buy a MTB. Problem solved. :sunglasses:

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Makes sense about the gear ratios, something I had not considered at all. I guess I will just have to wait and see what Shimano comes out with. Although nothing is in need of an upgrade right now. Hopefully we get something a bit more to my liking.

I was a bit ho-hum about a 12 speed announcement when it first came out. But after doing a deep dive on the gearing (and other aspects), there is no doubt in my mind, that pending successful user experience, this will wake up Shimano, and force their hand for a new drive train design, the benefits which trickle down to all of us including lower prices on existing designs.

Above I mentioned the advantages for a traditional compact user. For pros/elite athletes, the SRAM 50/37 with a 10:26 gives a similar 5.6% more leverage than a Shimano 52/36 compact and can achieve similar leverage at the low end. This is a BIG deal in hilly road races with long flat sections or with sprint finishes.

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Yep, I can for sure see it going that way. Will be interesting to see what everyone come out with in the next couple of years.

One of the issues for our friends at Shimano is how they do their trickle down. Take the following timeline for instance:

2019:

  • Red 12 spd AXS is released
  • April 2019 - Force 12 spd AXS is released

2020:

  • Shimano announces 12spd groupset for 2021

2021:

  • Shimano releases 12spd Dura Ace Gruppo

2022:

  • Shimano releases 12spd Ultegra Gruppo

I think the above is being generous to Shimano. So basically, we could be waiting 3-4 years before 12spd Shimano is being spec’d as mid range OEM. Big issue for them. If SRAM hit 12 spd Force out of the park in April, we could see them become the preferred supplier for mid range OEM.

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My take is a couple things…

Personally, as an ETap 11 HRD user, I’m glad the new version is ultra high-end with integrated chainrings/powermeters. I have to admit that it’s really nice to have great equipment and see the Pros on the true top-of-the-line stuff. Sometimes it feels like a bit of a piss take for me to be on the same stuff for what I get out to do on a bike as an amateur. So, leave the 12sp super chainring/powermeter gear for the Pros. I’m good with that.

The biggest thing about SRAM’s latest, in my opinion, is they’ve turned gearing on its head a bit with chainrings and cassettes. I’m confident we’ll see more freehub bodies accommodating an XD Driver type system with 10T cogs and 12 gears that isn’t married to the ultra high-end groupset.

The system was released last week. Give it a bit and we’ll see a ton of great innovation and adoption from 3rd parties to move us all into the ‘next level’ without killing our bank accounts.

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Di2 already does this. You can also tweak it to your personal preference using the e tube software

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I’ve been lucky enough to get a few short rides on the new system. The changes are a lot more consistent, which adds up to a big improvement in the feel of the system. Front shifts still feel slower the EPS or DI2, but rear is similar enough for me to not care about any difference. If you set it so that it shifts the front automatically as you move up or down the cassette, then the front shifts happen nice and quickly.
Frankly though, at this sort of money, it should be perfect. I liked a lot about ETAP - the wireless aspect made it so easy to set up bikes. It felt though that they had had a load of great ideas but not really executed a number of them well enough to justify their inclusion in the finished product. Hopefully all this fancy development will lead to trickle down improvements and greater competition in the mid range market

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When 3T came out with their 1x there were concerns that the smallest cog created significant friction losses, wonder if a 10T would have a similar problem?

Yeah I thought the same thing, and with one tooth less there must be an increase in wear.

Also the rear derailleur sems to hang out a bit more than the Shimano derailleurs, which would make it less aerodynamic.

DA:

SRAM:

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For me this is another fundamentally bad engineering decision. I can tell you that riding on the 10t cog on a XX1 cassette isn’t as nice as on an 11t. It is also less efficient since at the same power the 10t will have 10% greater force in the chain and will increase the bend angle.

Mike

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I think the chart listed might be incorrect. The weight listed for the Dura Ace shifter seems a bit light. I checked it on the Shimano site and it lists the hydraulic version at 538g a pair, which would bring it much closer to the SRAM.

I’m actually disappointed to see the cassette options top out at 33T. I would have thought a 10-40 or 42 for gravel riders would be a great option. The 50 is overkill but having a decent sized front ring is paramount for high downhill speeds, but can kill your climb if you’re too big. I’d love to use the 2x but the front derailleur blocks tires bigger than 42c.

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Agreed on lack of low end for gravel. I was hoping for a real under-gear option and that isn’t here…yet?

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Being able to use a remote shift button for the dropper post is a nice touch. It seem like 80% of an awesome gravel group. Did they purposely wait till the CX season is over so people wouldn’t ask? :smirk:

Are you saying that the eagle cassette is overkill for a 2x setup? For a 1x gravel option the Eagle rear derailleur and cassette seems like an awesome combo, being able to have the addition of the 50T onto an 10-42 11speed cassette. For me personally that would allow me to run a bigger front ring and still giving me more low end for steeper climbs.

Isn’t one of the advantages of AXS that MTB and Road components are all cross-compatible? So you could run an Eagle 10-50 cassette with road shifters?

I do hear what you are saying about 50 being too big though.

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