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AASQ #83: SRAM Shifts through your questions on gearing for gravel bikes

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We know, there’s no such thing as a stupid question. But there are some questions you might not want to ask your local shop or riding buddies. AASQ is our weekly series where we get to the bottom of your questions – serious or otherwise. This one dives into the world of 1x, 2x and other gear related questions specifically for gravel! Hit the link at the bottom of the post to submit your own question.

pricing and specs for sram force axs 43-30 wide range road and gravel bike group
SRAM’s new Force eTap AXS Wide Range gravel drivetrain with 43/30 crank and 10-36t cassette.

AXS

Eric: Will we see Force AXS or GX Eagle AXS?

SRAM: Great question, Eric. You can see Force AXS right now! SRAM introduced Force eTap AXS to the world on April 3rd, 2019. We then offered expanded wider gearing options for Force eTap AXS on May 13th, 2020. Eagle AXS has not made its way down to the GX level but do know we are constantly working to offer the marketplace new and exciting products whenever possible.

1x or 2x?

Paul S.: I have a single dropbar bike for Road, Gravel, and Cyclocross. I am not ready to lose my 2x gearing for road and most gravel, but I appreciate a 1x setup for some gravel and cyclocross. Is there a good option for me to run 2x most of the time, and swap to 1x with a spider/chain swap and removing the FD? Extra points if it doesn’t require a rear derailleur swap.

Andrew (reply to Paul): This is exactly what I do on my Super-X…. I have a Sram AXS 2x Setup that I run for the Spring/Summer for Road and Gravel Riding, then just swap to a 1x for the fall for CX season! Perfect!

Guy (reply to Andrew): What crankset are you using to swap between 2x and 1x? Or do you have two separate cranksets?

Andrew (reply to Guy): Sadly, 2 separate cranksets due to the silly PF30-83 BB. I have a Sram Red AXS Dub (Regular axle length) for 1x and a Force AXS Dub-Ai Crankset for 2x.

Neil: I’m a middle-age clydesdale rider who lives at the base of some pretty serious mountains. Gear spreads of 500%+ are a start, but to make gravel really work off and on roads, I need 700-800% in order to be able to spin a super low gear up steep fire roads and still keep pace with car traffic on canyon road descents. I’m asking for something functionally similar to Eagle cassettes with an extremely compact 2x crank. Is something like that possible?

SRAM: Hi Paul- This is a solid option with eTap AXS components. For road eTap AXS electronic 12 speed gearing, the rear derailleur is equipped with the Orbit fluid damper system to reduce chain bounce, so it works with both 2x and 1x set ups. If you have a Force crank spider, you can swap between 1x and 2x by changing chainrings and chainring bolts, and ideally having separate chain lengths for each configuration. For mechanical gearing, clutch equipped X-Horizon straight parallelogram rear derailleurs are built to be utilized in 1x configurations only. Mechanical 2x rear derailleurs for road are not clutch equipped, so they lack this chain retention feature and are generally meant for 2x setup only. Maximum cassette size for a road mechanical medium cage WiFLi rear derailleurs is 32t. There is not a compatible 2x option for cassettes in the Eagle range.

 

Adrian: If one has a gravel bike that could take an Eagle AXS 1×12, 48 front and10/50 cassette, or an AXS 2×12,46/30 front and a 10/36 cassette; what criteria would one use to choose?

SRAM: Hi Adrian- great question. The 2×12 eTap AXS system offers a 13t jump between chainrings- so presuming you are interested in the 46/33t with a 10-36t cassette, you’d get 502% gear range with a sub 1:1 gear ratio (.917). With a 2×12 AXS system, you can make smaller adjustments in the back so when you do shift the front, it’s easier to return to a comfortable cadence.

For an Eagle AXS setup with a 48t chainring and 10-50t cassette, you get a 500% gear range with a gear ratio down to .96. We do now offer a 10-52t Eagle cassette that is compatible with Eagle AXS derailleurs- for a 520% gear range and down to .923 gear ratio. If simplicity of setup with less components to maintain and adjust is your thing, 1x may be the way to go.

sram force axs 43-30 wide range gravel bike group complete technical details and specs

Lower Gearing?

Oli: Is there an option in your crankset/chainring lineup for very low ranges? Do I need a MTB crankset? I’ve found that the 42t front ring on my Apex crankset is far too high for me and my riding, I’d like to experiment with 36t or 38t chainrings but it’s pretty hard to find out online what works with my bike (Lauf Anywhere).

SRAM: Hey Oli, great question. Apex 1x cranksets have a specific 4-bolt chainring that mates to an asymmetrical spider. Chainrings for Apex 1 are offered in 40t, 42t, and 44t only. However, you can go as low as 38t and high as 50t chainring with a compatible Rival 1 or Force 1 crankset with a 5-bolt 110mm BCD.

why did SRAM change the chainring sizes and gear combinations on their new RED 12 speed road bike group

Low Gears with Power Meter?

2TurnersNotEnough: As a numbers geek, I like having my Quarq power meter. What are my options to get sufficiently low gearing for gravel riding on a 2x drivetrain, while being able to run a crank-based power meter?

SRAM: With 2x power meters for eTap AXS, you can go as low as 46/33t for our 4-bolt, asymmetrical 107mm BCD power spiders. We offer a 36t compatible rear derailleur with our Force eTap AXS drivetrain, with a 10-36t cassette option, offering a 502% gear range with a sub 1:1 gear ratio (.917).

For 11 speed and lower, Quarq offers DZero power meters in both a 130mm and 110mm BCD spider- allowing for rings as small as a 46/36t chainring combination. Using a 2x WiFli rear derailleur with an 11-32t cassette will offer a 372% range with a 1.13 gear ratio. A 50/34t chainring combination will get you even lower with a 428% range, and down to 1.06 gear ratio.

SRAM AXS UserVoice_wireless end user AXS access platform feedback mobile app web functions

More speeds/Intercompatibility?

Fabiano: Hypothetically, when SRAM goes to 13 speed, can the drivetrain can be reprogrammed for that or we need to buy a new groupset upgrade?

Pete: When are the 14-speed cassettes dropping?

Erik: Remember when SRAM’s ten speed derailleurs could be used with road or mountain or cyclocross shifters? Those were the days. Why on earth would you make your twelve speed chains completely incompatible?

SRAM: Good question, Fabiano. Let’s talk about the requirements to upgrades when it comes to newly developed drivetrain. Because we are now in a firmware-features-update kind of world, it’s understandable that some would expect that a quick firmware update would allow for greater gearing options in terms of drivetrain. However, there are physical factors at play with previous generation electronic-equipped bicycle parts that do not allow for compatibility to the newest systems in some cases – with similar concerns as mechanical drivetrains.

Changes to the drivetrain such as chainring width, physical features of the chain, chain width, roller size, cassette cog spacing, and freehub body compatibility are all physical factors in changes to drivetrain that may not be compatible with previous generation componentry. While we can’t offer any details on a possible 13 speed and beyond as far as compatibility with previous generation components, this is a factor to keep in mind when new drivetrain components are introduced.

sram force wide range 10-36 cassette for gravel bikes and road bikes

Cassette Gearing?

Seb: I’m a 1x fanboy and on 11s the 420% range 10-42 cassette hit the sweet spot for many but there is no similar option for 12s. No I don’t want to use a front derailleur and I don’t need the range of the Eagle cassette but would rather have the 420% with smaller jumps between the gears. Are you planning to fill this gap?

Kyle: Is SRAM going to offer AXS cassettes in intermediate ranges (high 30s-mid 40s) for those looking to optimize gear steps and ratios for flatter terrain?

Guy: For 10 years SRAM has been telling us the off-road front derailleur is dead – and I’m fully onboard with that! But I want more range than 10-36, less than 10-50, and want to use AXS on my gravel bike. When are SRAM going to launch AXS 10-42 and will it use the road or MTB chain specification?

dking1525: 12t cassettes:
10-50t;10,12,14,16,18,21,24,28,32,36,42,50 SRAM XG-1299 Eagle
10-42t;10,11,12,14,16,18,21,24,28,32,36,42 SRAM Why does this not exist?
10-33t;10,11,12,13,14,15,17,19,21,24,28,33 SRAM RED XG-1290

SRAM: Seb, we recognize the opportunity to fill the gap in gearing within our product families. Our product teams are always looking to improve our offerings, as gearing is a very important part of our drivetrain development. Stay tuned for further updates in this area.

3T Aeroflux aero road bike dropbar, 3T Strada Concept 3, limited edition aero 1x carbon road bike, Superflux LTD road handlebar

1x for Road?

Thor29: I think there is a fairly large demand for a mechanical road 1x system that uses 12 speed mountain cassettes. Such a setup would allow a low enough gear for loaded touring or super steep off road climbs without giving up too much top end. So when is it gonna happen? Make a version that works with mechanical disc brakes and I will buy it. (No electronics or hydraulics for me).

Caesar: Literally any serious road cyclist that do not ride on a pancake-like area. Hated the 1x groups, the experience SRAM and 3t forced into their pro team has been an absolute disaster. For recreational rider or super flat area, yes.

SRAM: 1×11 is really great for a lot of people and a lot of applications. But it was never intended to cover the range needed for professional road racing, especially in the high mountains, where pros need super small and super heavy gears, but still want the small jumps between the gears. Aquablue and 3T were just too early to the party. A 1×12 AXS system using a 48t or 50t front chainring, combined with a 10-36t cassette would make for small enough jumps between the gears at an overall range suitable for pro racing.

pricing and specs for sram force axs 43-30 wide range road and gravel bike group

Chain length between 1x/2x?

Sebastian: Not really a specific gearing question, but up the same alley. I have 1 do it all bike the I am very pleased with. I swap wheels between all out road and gravel and have different cassettes on the two wheels but keep the same 46 tooth front ring. The gravel cassette have a largest cog of 36 teeth while the road cassette tops out at 28 teeth. Can I run the same (length) chain on both wheelsets and if so how do I find a good compromise between the two optimal lengths for each given cassette? What are the downsides to this? Also generally what downsides are there to using a long cage rear derailleur with a small cassette. Thanks

SRAM: Hi Sebastian – Proper installation is key to a properly functioning drivetrain system, and chain size is critical. You didn’t mention which level drivetrain you are using, but in all cases, chain sizing for drivetrain is the same for 1x: road 1x rear derailleurs – and eTap AXS rear derailleurs being utilized in 1x setups – require 2 inches (2 inner and 2 outer links) of additional chain after wrapping “big-big” (big chainring front/ big cog in the rear, bypassing the rear derailleur) when sizing the chain, pre-installation. Your chain size will need to change with a variant of 8t that you have between your two cassette sizes. Because of this size difference, there is not an optimal chain size for both cassettes using the same chain.

The downside of running too long of a chain is improper pulley cage retention that fails to keep the chain properly tightened across smaller cassette cogs. The downside of a chain that is too short is possible chain jam. A chain jam can occur with a too short chain when shifting to the larger cogs- essentially there will be not enough chain to wrap around the cog while also passing through the derailleur pulley cage. The worst-case scenario in this instance is where a pulley cage over-extends and gets pulled into a rear cog, jamming your system further. Force pedaling this jam (or any chain jam, stick or otherwise) will further force the derailleur cage into the cassette where it will either twist, or break entirely. Check out our service page for some super helpful technical manuals and installation guides here: https://www.sram.com/en/service

One other thing to note: a “long cage” road 1x rear derailleur has the same overall cage length (distance between pulleys) as a “medium cage”. The placement of the pivot point of the cage assembly is different between these versions, which means they have different clearance compatibilities with different sized cassettes (36t max for medium cage versions, 42t max for long cage versions).

Got a question of your own? Click here to use the AASQ form to submit questions on any cycling-related topic of your choice, and we’ll get the experts to answer them for you!

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13 Comments
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paochow
4 years ago

Pardon me, but you forgot to address the numerous questions about 1×12 mechanical…..

blahblah1233445
4 years ago

There were 2 questions repeated constantly by different people and those were about mechanical 12s groupsets and wider range 12s cassettes (but smaller than eagle ones). The first question was just completely omitted, the other was answered “stay tuned”…

Seriously SRAM – if You’re doing Q&A stuff, at least have some courage to address the most common and important problems, instead of just the ones that You feel comfortable about.

Jason
Jason
4 years ago

No, you will find so many people (Sicycle forums) who wish since months a mechanical SRAM 1×12 – but SRAM doesn’t reply in any way. But as you might know, there are possibilities to “hack” rebuilt the 1x 11 shifters…

Paochow
Paochow
4 years ago
Reply to  Jason

Jason- any tips you can share on hacking the 11sp to 12sp?

Jason
Jason
4 years ago
Reply to  Paochow

you just need a 12th ( it is even possible with a 13th) “index”/ notch inside the mechanical shifter.
see here:
comment image&hash=cf7e833816fb1fc505065d7cd1543b64

Pao
Pao
4 years ago

For a family of riders, I’ve now bought twelve 11-speed e13 cassettes since SRAM hasn’t released a 12sp mechanical. I’d love to switch to 12sp and run a SRAM 10-50 cassette on all our bikepacking rigs, but sorry there is no way I’d ever depend on a battery powered rear derailleur. I really hope you consider releasing one as there are a lot of bikepackers that would buy a mechanical 12sp groupset.

Ron
Ron
4 years ago

So lame that they dodged the many questions re: mechanical drivetrains. So very lame. I hope that Campagnolo’s new Ekar 1 x 13 group will really clean up, since SRAM is too arrogant to respond to what the public actually wants.

TheKaiser
TheKaiser
4 years ago

Maybe you have already seen this, but there are one or more people offering modified internals for SRAM 11spd rear shifters that convert them to 12spd or even 13spd. Basically, its new ratchet parts with an additional notch or 2. It’s not cheap (a few hundred dollars or euros from what I recall), but still less than a whole new groupset. I think the last article I saw featured parts from a guy in Germany.

Jason
Jason
4 years ago
Reply to  TheKaiser

…costs are about 100 € .

Cal C
Cal C
4 years ago

90% of questions to SRAM were very reasonably asking for a 12 speed mechanical road shifter. The cassettes exist, the derailleurs exist – it’s literally just making the indexing different in the 11 speed shifter, so just do it already!

Adrian Engel
Adrian Engel
4 years ago

Paul Components in California make an adapter that allows one to attach a Sram Eagle mechanical thumb shifter to a drop road bar. It works. I have used it. https://www.paulcomp.com/shop/components/drivetrain/shifting/sram-shifter-adaptor/

Adrian Engel
Adrian Engel
4 years ago

I forgot to add that I used TRP brakes to complete the build as no brake/shift levers were needed. I used https://trpcycling.com/product/hylex-rs/ but they have a mechanical option as well. I was quite satisfied with their brakes.

Hexsense
Hexsense
4 years ago

My perfect gravel gearing?
Gearoop 44/28 front chainring direct mount to Sram crank arms.
pair that with 11 speed, 11-32 cassette in the back.

I’m not strong enough to require 44/11 on Gravel anyway. But 28 front 32 rear is useful.

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