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Di2 vs. AXS: The quick guide

By Bruce Lin

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Shimano Di2 vs. SRAM AXSSRAM Red eTap AXS on the road | Photo: Chris Milliman

We may soon witness the death of the mechanical drivetrain. Electronic shifting has become refined and reliable. Electronic drivetrains are used throughout the pro peloton and increasingly available on new bikes.

Maybe you’ve learned all about the advantages of electronic shifting or you’re just a gear geek who wants to stay current. Either way, there’s good reason to ditch the cables on your next bike. But how do you decide between a Shimano Di2 group and a SRAM AXS drivetrain? Each has different features, pros, and cons. Here’s what you need to know. 

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Shimano Di2 vs. SRAM AXS price and weight comparison

Shimano Dura-Ace Di2 vs SRAM RED eTap AXSThe latest and greatest: Shimano's Dura-Ace Di2 and SRAM's RED eTap AXS XPLR rear derailleurs.

The tables below feature the latest hydraulic disc brake drivetrains from each brand. Prices are based on retail pricing; if you find it cheaper online, more power to ya! Weights are based on the manufacturer’s claimed weight.  

These tables only compare electronic components like shifters (including brakes for road shifters), derailleurs, and batteries. Components such as cranksets and cassettes have been omitted. These tables will give you a rough idea of how much cost and weight the electronics add to a complete bike. 

Road

Shimano

Price

Weight

SRAM

Price

Weight

Dura-Ace Di2 R9200 

$3,038

947g

RED eTap AXS 

$2,360

1,215g

Ultegra Di2 R8100

$1,979

1,089g

Force eTap AXS 

$1,565

1,324g

N/A

--

--

Rival eTap AXS

$1,150

1,391g


Gravel

Shimano

Price

Weight

SRAM

Price

Weight

N/A

--

--

RED XPLR eTap AXS

$1,960

1,067g

GRX Di2 RX800

$1,342 (1x) / $1,569 (2x)

1,133g (1x) / 1,264g (2x)

Force XPLR eTap AXS

$1,340

1,155g

N/A

--

--

Rival XPLR eTap AXS

$975

1,197g



Mountain

Shimano

Price

Weight

SRAM

Price

Weight

XTR Di2 M9000

$1,210 (1x)

436g (1x)

XX1 Eagle AXS

$1,000

441g

XT Di2 M8000

$689 (1x)

505g (1x)

X01 Eagle AXS

$800

458g

N/A

--

--

GX Eagle AXS

$600

522g


Bottom line: Di2 is more expensive than its AXS competition. For road applications, Di2 is notably lighter. 

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Wires vs. wireless drivetrains

Shimano Dura-Ace R9200 Ultegra R8100 Di2The latest generation of Di2 uses wires with easier to install wireless shifters. | Photo: Shimano

Shimano Di2 uses wires to connect the battery, shifters, and derailleurs. SRAM AXS is fully wireless. The latest Dura-Ace Di2 R9200 and Ultegra Di2 R8100 drivetrains are hybrid, using wireless shifters. 

Wired advantages 
  • Fastest shifting, although the difference is imperceptible to most.
  • A central battery that provides a longer run-time
Wired disadvantages
  • Requires frame compatible with Di2 wiring.
  • Installation can be difficult and time-consuming. Once installed, it’s set and forget. 
Wireless advantages
  • Extremely easy to install on any frame. 
  • Provides a clean, cable-free look.
Wireless disadvantages
  • Multiple smaller batteries (one per derailleur) that require recharging more often.
  • Bulkier derailleurs due to the battery. 

Bottom line: Both shift quickly and reliably. Once set up, both are very easy to live with. If upgrading an older bike, AXS will be easier to install for most home mechanics. 

Batteries and charging

SRAM AXS battery chargingThe SRAM AXS battery in a recharging cradle. | Photo: SRAM

Shimano Di2 battery life: at least 1,000km (621mi)

  • In practice, an average cyclist that rides three to five times a week will only need to charge their Di2 bike about four times a year. Full charge in about 1.5 hours. 

SRAM AXS battery life: approximately 60 hours of ride time 

  • AXS batteries take an hour to fully recharge. Because the batteries only weigh 25g, it’s possible to carry a spare. You can swap batteries between the front and rear derailleurs or an AXS dropper seatpost if one dies. 

Bottom line: The two brands use different metrics to measure battery life so it’s hard to compare them. What’s more important is which battery style you prefer.

Shift customization

Shimano Di2 E-tube project appMake adjustments with the Shimano E-Tube Project app. | Photo: Shimano

Both Di2 and AXS allow the addition of small accessory  “sprint shifters,” “climbing switch shifters,” or “blips.” Both Di2 and AXS can connect to a smartphone app to customize shift preferences like Synchro (Shimano) or Sequential (SRAM) shifting or Semi Synchro (Shimano) or Compensating (SRAM) modes. 

Bottom line: It’s a tie.

Gearing and speeds

SRAM AXS X-range gearingX-Range vs. traditional gearing. | Photo: SRAM

12-speed Shimano Di2 road drivetrains offer “standard” gear range that most experienced cyclists will already know. SRAM’s AXS road groups have switched to “X-Range” gearing with smaller chainring sizes and wide-range cassettes. For road, AXS X-Range provides the easiest low gear (43/30t chainrings + 10-36t cassette vs. 50/34t chainring + 11-34t cassette). 

Shimano’s GRX Di2 gravel drivetrain is currently 11-speed and can be run as a 2x or 1x. SRAM’s gravel-specific XPLR drivetrains are now 1x only with a 12-speed 10-44t cassette. Gearing depends on chainring selection, usually 40-44t. 

Shimano does not offer a 12-speed Di2 mountain bike drivetrain using its wide-range 10-51t cassette. Its widest range cassette is an 11-speed 11-46t. SRAM Eagle AXS mountain bike drivetrains are all 12-speed and work with 10-50t or 10-52t cassettes. 

Bottom line: If you like old-school 2x go with Di2. On the MTB side, SRAM Eagle AXS has no real competition … yet.  

Clutches and chain management

SRAM GX Eagle AXS overload clutchAll Eagle AXS derailleurs from GX to XX1 feature the Overload Clutch. | Photo: SRAM

SRAM RED and Force AXS rear derailleurs use Orbit Fluid Dampers to prevent dropped chains and chain noise on rough roads. The Orbit Damper is ​​lightweight, low friction, and speed-sensitive. The harsher the bump, the more resistance it applies to keep the chain under control. Rival AXS rear derailleurs use a more traditional mechanical clutch. 

SRAM Eagle AXS mountain bike rear derailleurs use a standard roller bearing clutch but add an Overload Gearbox Clutch to protect the derailleur and motor during an impact. The Overload Gearbox Clutch disengages, giving the derailleur freedom to move and absorb the impact, saving you a hefty repair bill. It quickly reengages and the derailleur will realign itself in a split-second.

The latest generation 12-speed Shimano Dura-Ace and Ultegra Di2 drivetrains currently don’t offer a clutched derailleur option (the previous generation had the clutched Ultegra RX). The gravel-oriented GRX Di2 rear derailleur uses the same clutch mechanism as the rest of Shimano’s mountain bike derailleurs which can be toggled on or off. 

Bottom line: If you ride rough roads, gravel, or trails, SRAM AXS has the latest clutch technology. Pure roadies probably won’t care, though. 

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Final thoughts

There are pros and cons to each system. Here’s what I think:

  • AXS for MTB
  • Di2 road for weight savings
  • Di2 for battery life
  • AXS for 1x simplicity/ease of install/upgrading any bike
  • AXS for climbing gears

Do you like Di2 or AXS? Why do you prefer one over the other? Let me know in the comments!

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5 comments


  • “We may soon witness the death of the mechanical drivetrain.”

    Soon? Unlikely. Maybe at the upper end of the offerings but Big Greedy Bike Companies will still want to sell “price point” bikes to newbies who will chafe at having to pop for a $5000 toy. Mechanical will die only when the profit margin says it can. And nothing ever “dies” completely. You can still get friction shifters, lugged steel frames, threaded headsets, quill stems, square taper BBs, freewheels, etc. even decades after these things have been deprecated by “the industry”. Harder to get, sure, but still “alive” and out there.

    As to Shimano vs. SRAM: As a life-long road cyclist, I learned long ago that nothing beats Shimano products for functionality and reliability. If they’re still using wires in their electronic shifting setup you can bet that there is a darn good reason for it.

    Hoogle Da Boogle on

  • Hi
    You never try the Campagnolo 12×2 mechanic Groupset? This is precisely like a Swiss Watch, and shifts fast like a gunshot!
    For Persons they have an Electrosensibility those Blue Tooth Groupsets are for nothing! But the Industry don’t take care on those People!!!
    Regards Roger

    Radsport Gross Roger Gross on

  • While I agree with the point of having a bottle in your hand is difficult with AXS, I found it much more difficult to find the slim finger positioning between the shifter buttons on Di2 than just pressing one button per shifter on AXS. On the Di2, when I was focusing on fast gear changes I often would hit the wrong button which was extremely frustrating when you were in a cadence rhythm. One other item that frustrated me with Di2 is cabling. Somehow my cabling from my shifter got pinched in the head tube routing and there went my shifting. With AXS, that’s not a concern. I’m a Shimano fan who hated DoubleTap, but after trying Di2 and then loathing it, I prefer AXS, because it just feels more like riding my bike than a tech experiment.

    Jason Miller on

  • I have two Orbea Orcas, a 2019 with Dura Ace Di2 and a 2020 with etap AXS. There is just no comparison between the two and the Shimano product is radically superior in my opinion. Granted, the Dura Ace is a higher quality position in the line and the Etap AXS. Nonetheless, the shifting is radically faster and clearly noticeable with the Shimano product and it does not to be tuned and adjusted regularly The way the SRAM product needs to be. Far more importantly however, I ride hard and I drink while riding. That really is far more difficult with the SRAM product than it is with the Dura Ace product given the different configuration of shifting. With the dura Ace product I can hold my water bottle in my left hand and makeshift up and down my rear cluster while drinking. Making small adjustments for varied terrain while riding the orca with the SRAM equipment is really not possible in the same respect. For me, the difference is a game changer.

    David Gerstenhaber on

  • I’ve been very happy with our Shimano Di2 Ultegra’s. I switched out the Dura Ace that came with the bike to the Ultegra to add 32T rear socket to my Cannondale Super Six EVO due to the very hilly terrain in our area. A year later, I purchased a Cervelo R-3 for my wife. This came with the Ultegra but we added the longer cage and 32T rear socket. The socket change made a huge difference in the enjoyment level of the bikes. The Di2 have been flawless in their operation and even 4-5 years after the purchase the battery life is amazing. When Shimano comes out with the wireless with the Ultegra or has the capability to add the longer gear cage to the Dura-Ace I’ll be all over it.

    John A Cannon on


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