I did a little research, and found this article : https://velo.outsideonline.com/...-and-2x-drivetrains/

I would have really liked to see a 2x SRAM included in this comparison, but I suspect that the losses on the higher cogs will still be the same

if you want to go wireless blips without blipbox, you need someone to loan you a pair of shifters, or a blip box, for the pairing.

ZFC is in agreement with the testing done from ceramicspeed/friction facts which reports a 2 watt loss at the lower gears (48x42 vs 39x34) , and a 6 watt loss at the higher gears (48x10 vs 53x11). This can be mitigated if you run the 50T chainring, or the ultra rare 'pro' version of sram red.

SRAM AXS chains are also slow. 2-5 watts slower at 250 watts versus other brands. Combine the two and you are looking at anywhere from 2-11 watt loss depending on the circumstances.

Solution: I am running SRAM AXS force but with a ROTOR crank, a YBN chain, a Shimano cassette, and I swapped out the original pulley wheels.

I was planning on buying a cheap rival shifter, and keep it for the pairing.

Your solution is very interesting, you mean that you actually use the "mechanical part " of Shimano 12 speed, but the "Electric part" ie shifters, front/rear deraileurs are sram force ? Does it work fine?

Could you please share with me the chainring and cassette you chose ?

No, you don't :-) Just get a recent firmware. You have to set Microshift via app, of course. I swapped Shimano 105 mechanic to SRAM on my Felt (Force rear derailleur, Rival front derailleur and crank with powermeter, RED cassette, Force Chain, 2 pairs of Blips) - except the brakes (kept the TRP) and pedals (Dura Ace). It works without any system/central controller, just pair everything by pressing the AXS buttons on the components in the right sequence and config the Blips via the AXS app.

I ordered rival front/rear derailleurs, a set of wireless sram blips, ultegra crankset, dura ace chain, ultegra cassette, ultegra jockey wheels.
I really hope I can sync them withouth a shifter/blipbox and that it will shift perfectly.

My real fear is that SRAM stops production of blips in a few years and I will be left with a pile of garbage.

I am baffled. In a relatively new youtube video SRAM states that you need a controller. So I wrote their customer service if they want to correct it.
They have been quite surprised and asked me for details: components, firmware version, maybe a video connection everything.
Iow: Using everything without a controller is currently not officially supported. But it works for me.

Where do you see that? There was one CyclingTips-reported test where brand new chains started about that much slower, but the after just ~10-15 hours on the test rigthey started to converge towards Shimano in efficiency. This was for both Red and Force AXS. I was bummed they didn't run them longer. That test graph is now lost somewhat lost in the internet due to Outside killing CyclingTips, so no screenshot until I can use Internet Archive or something to track it down.

The ZeroFriction stuff is hard to interpret as they give a 0-5 scale, not W, and the protocol isn't totally clear. But on their 0-5 scale, the Force AXS with ZeroFriction special lube matches Shimano Dura-Ase 12s. Red is one tick slower, whatever that means. But I wonder about run time given in the old CyclingTips-reported test Force started faster than Red, but looked like Red was going to catch up over time.

Long story short, I'm not sure relative efficiency of SRAM 12sp chains is a totally settled thing. Oddly, given they've been around for a while.

SRAM factory grease: nuke it from orbit as soon as you get a new chain. But I think we all do that now anyway.

Force AXS matching Dura-Ace with cleaning and super-l00b:

Well, if I can't do it withouth a controler, I will try to sync at a LBS, and if not I might even buy that damned ripp off blipbox (unless there is something I don't see to explain why this thing costs 400$).

Mixing Rival and shimano 12s was quite cheap, less than 1000€ to change everything except brakes. I will report to tell if this configuration works or not.

You can use a Pod for aboud 120 bucks. That was my plan until I saw that I don't need a controller, so I sent it back.

Any issue with sram FD working on larger tooth cranksets? The standard max for sram axs FD is 50t. If you get the larger red axs chainrings, they come with a dual mount FD to be able to raise the FD higher. Am i missing something for a standard axs FD to work on 53t shimano crank?

I think all you need is a shifter with a pairing button OR a blip box, so you could grab a Apex AXS shifter for $220 instead of the blip box, unless I'm mistaken.

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

That is my understanding as well, but If having a shifter/blipbox is required on the bike, I'd rather have the blipbox in order to use the wired blips and not worry about the battery of the wireless blips comes race day.

but you don't need to have the shifter permanently on the bike, just within pairing range while you set everything up.

edit - nvm I saw your point about battery and wired blips

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

Similar to mine, AXS Force RD w/ Kogel cage/pulleys, using a Shimano cassette, YBN chain, and a 54T aero ring on a SRAM crank.

If what has been mentioned in this thread is correct, you don't need a separate shifter to pair the wireless blips... that's really great news!

I have Sram red AXS on both my tri and road bikes with a 55 Rotor Q-ring on my tri bike and a 53 Rotor Q-ring on the road no dramas. I know a lot of pro cycling teams in Europe run 53 Sram rings or the like.

Correct but can it done with force axs FD? Just curious because I couldn’t find anything definite online. Posts i found were all with red axs FD

what that test doesn't consider is the gearing. Theres a Ceramicspeed/Friction Facts study done with Velonews that studied this.

If you stick on the sram chain (which only works on the sram system) then you are paying a penalty for the power loss from not only the chain but the tension in the chain from gearing.

I am sure the cage design and mount orientation is no different. They serve the same function.

yes, you need to be careful with this.

I run 52T Rotor Q rings and my Force FD did not clear the chainring when shifting. Depending on frame you MAY be able to get away with this.

the Solution I got was to get a FD extender. depending on your chainring setup a shim to move the FD backward or change the angle might be enough for you.

thank you. this is the information i was looking for. The red FD have dual mount holes to allow larger chainrings since sram only offers a larger axs chainrings in red level.

davidalone wrote:

what that test doesn't consider is the gearing.

That test shouldn't consider gearing because it's a test of chain efficiency.

Quote:

If you stick on the sram chain (which only works on the sram system) then you are paying a penalty for the power loss from not only the chain but the tension in the chain from gearing.

Except maybe there is no real loss from the chain. Could be, I just haven't been convinced yet.

The other three main sources of drivetrain drag could be:

1) Cross-chaining losses (context dependent)
2) Chain articulation on smaller cogs (what I think you're calling (tension in the chain). (context dependent)
3) Actual chain tension - a function of RD springs, etc.

For the first two, a SRAM TT rig could do just fine. You'd just have design it so that chain lines and cogs you'd actually use are TT-optimal. What I'm calling "context." World Tour pros do this. It can seem like a bit of a waste to have a 10t cog and essentially never use it. I get that. But it doesn't mean the system can't be just fine.

For 3), chain tension losses are another thing we don't know a ton about. The Friction Facts guys did good work on this before moving to CeramicSpeed, but since the move I don't believe there's any publicly available testing results from the latest generations of RDs.

A little update : it works, and I didnt need a shifter to sync the wireless blips with the rival etap deraileurs. However, it took me more than an hour, the app is clearly not intended to configure it this way.

I was not able to swap the rival jockey wheels with the shimano 8100, they are too wide.

List of components :
Sram etap rival front and rear deraileurs, batteries and charger
One pair of wireless blips
Ultegra cranckset 52/36
Bb86
Dura ace 12s chain
Ultegra cassette 12s, 11-30

Tried it for an hour on zwift, working perfectly for now, It should be fine outside too.

Thanks everyone for the help

glad it worked out. sorry if I missed it, but why are you mixing sram and shimano components? I thought you had to use a flat top chain with the 12-sp axs sram system

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

I do not want to have a friction loss (sram ), and I don't want a single cable on my bike (shimano), so I took the best parts of each system. The best aspect of this build is that the whole group was around 1000€, which is much cheaper than I expected