Shimano Dura-Ace vs SRAM Red: groupsets compared

New Di2 vs eTap, hydraulic braking, power meters and more

With the release of its new and multifaceted R9100 road group, Shimano has upped the ante significantly, pitting its top-tier Dura-Ace against the likes of SRAM’s also-diverse Red group. Here we compare the two groups, in all their mechanical, electronic, hydraulic and power-measuring configurations.


While Shimano’s leap forward with electronic programming and power measurement is the big story, the Japanese company’s refinement of its mechanical componentry is noteworthy, too.

SRAM has not completely overhauled its Red 22 mechanical group since its launch in 2013, but there have been some tweaks like new graphics and a front-derailleur shim for improved shifting.

Mechanical comparison: Shimano R9100 vs SRAM Red 22

Shimano Dura-Ace mechanical vs SRAM Red mechanical
Shimano Dura-Ace mechanical vs SRAM Red mechanical:

Both Shimano R9100 and SRAM Red 22 are 11-speed, each with multiple options in crank length, gear combinations and cassette configurations.

In addition to cosmetic changes, Shimano reworked both mechanical Dura-Ace derailleurs for improved functionality. The 69g FD-R9100-F front derailleur now matches SRAM Red 22 in weight.

Shimano’s new rear derailleur, RD-R9100, is 158g (compared to Red 22’s 145g), but the big news is its direct-mount compatibility and Shadow profile. Shadow is a technology Shimano has brought over from its mountain bike groups that tucks the rear derailleur closer to the cassette.

Shimano also has a new 11-30t cassette that works with the new R9100. SRAM is no stranger to wide-range cassettes — its 1x groups boast up to 10-42t. SRAM offers its Red 22 rear derailleur in short and medium cage versions. The Red 22 rear derailleur with a medium cage can handle cassettes with an 11-32t range.

SRAM Red 22’s shifters are still substantially lighter than the new Dura-Ace (280g to 365g for the pairs). And each group has its own method of shifting. Dura-Ace retains the Shimano style of an inner lever to move the chain to a smaller cog or ring, and pushing the brake lever inwards to move the chain onto a bigger cog or ring. SRAM, meanwhile, uses what the company calls DoubleTap: a short press of the inner lever moves the chain to a smaller cog or ring, while a further press of the same levers moves the chain to a bigger cog or ring.

SRAM Red’s front derailleur does not need to be trimmed, which means a shifting adjustment to prevent chain rub on the front derailleur cage as the rear derailleur moves around. Shimano has two front derailleur trim settings.

Rounding out new the R9100 are a newer version of the existing Dura-Ace SPD SL pedal, plus new C40 and C60 carbon wheels. SRAM does not make pedals, but its sister company Zipp has a wide variety of wheels.

  • Shimano R9100 mechanical group – 2,007g – $2,029 / £N/A
  • SRAM Red 22 mechanical group – 1,747g –  $1,944 / £1,579

Electronic comparison: Shimano R9150 Di2 vs SRAM Red eTap

Di2 is Shimano’s terminology for its electronic componentry, whether on road with Dura-Ace and Ultegra, or on the mountain bike XTR and XT groupsets. This is nice and clear. Not so clear is Shimano’s use of numeric references, which have changed somewhat for 2017. While 9000 and 9070 refer to current mechanical and electric Dura-Ace, respectively, Shimano is now moving to a “50” suffix for electric Dura-Ace that has rim brakes, and is reserving the “70” suffix for electronic-shift/hydraulic-brake Dura-Ace.

SRAM is simpler. If it’s eTap, it’s electric and wireless. If there are disc brakes involved (see below), then its HC eTap.

As with 9070 Dura-Ace Di2, Shimano’s new R9150 electronic group is still wired from the single battery to both derailleurs and the junction box. What is new is the addition of Bluetooth to the system, so you can adjust the setup with a smartphone or tablet instead of just a PC (sorry, Mac users) with the 9070 group.

R9150 can also talk wirelessly to ANT+ peripherals like your Garmin Edge or other GPS computers. But there are still wires.

The big news with 9150 is the shifting-configuration options

The big news with 9150 is the configuration options. Soon after Di2 first came out, the boutique US shop Fairwheel Bikes hacked the system to perform sequential shifts via a circuit board. Instead of the rider having to shift the front derailleur and then adjust the rear as the gears went up or down, the Fairwheel system simply offered up or down buttons, and the circuit board did the math and the shifting.

Now, Shimano has basically that option as stock, called Full Synchronized Shift. Set up this way, the rider can use one button on one shifter to move all the way up through all the possible gear options sequentially, and the other button to move down.

There is also Semi Synchronized Shift, which lets the rider adjust the rear by a gear or two as the front derailleur shifts to minimize the change in the gear ratio.

All of this — plus the speed of shifting, and which button does what function — can be controlled by Shimano’s E-Tube software, now available as an app as well as PC software.

SRAM’s Red eTap system is simpler: there is a single set speed, and a single shifting protocol. With eTap, there is only one shift paddle button per lever. Pressing the right-hand shift paddle moves the rear derailleur outboard. Pressing the left-hand shifter moves the rear derailleur inboard. Pressing them both at the same time shifts the front derailleur (from the small ring to the big ring, or big to small).

SRAM Red eTap is wireless, so each derailleur has its own rechargeable and interchangeable battery that snaps on, and each shifter has a coin battery. Should one battery die on the road, you can swap batteries back and forth, or even carry a third spare battery.

Shimano has a single battery. When it runs low, the front derailleur stops working in the small ring, and the rear derailleur continues to shift for 100+ movements.

Both systems can communicate via ANT+ with compatible third-party computers.

Both systems have satellite shifter buttons. Shimano has tiny ‘sprint shifter’ buttons that can be positioned on the drops and function like eTap shifters: the right one moves the rear derailleur outboard while the left moves it inboard. Shimano also has a big two-button ‘climbing switch’ that can be programmed however you like. SRAM has ‘Blip’ satellite buttons that function like the pedal shifters on the levers. And both systems have time trial/triathlon shift options as well.

Both systems share cranks, cassettes, chains and brake calipers with their mechanical siblings. Both systems are also compatible with lower-tier components from the same company. For instance, you can use a Shimano Ultegra or 105 cassette or chain with Shimano Dura-Ace R9100 drivetrain, or SRAM Force or Rival brake calipers or crank with eTap parts.

  • Shimano R9150 Di2 group – 2,051g – $3,046 / £N/A
  • SRAM Red eTap group – 1,970g – $2,817 / £2,130

Hydraulic/electronic comparison: Shimano R9170 vs SRAM Red eTap HydroHC

After a long test period (BikeRadar spied prototypes in Chicago more than a year ago), SRAM recently announced its electronic/hydraulic group Red eTap HydroHC. Beyond the expected combination of eTap shifting with hydraulic disc braking, SRAM rolled out a few cool features with this group, including pad contact adjust. (All other road hydraulic groups are not micro-adjustable for where in the stroke the pistons connect with the rotors.)

Shimano has had electronic/hydraulic groups in two varieties for some time, but did not deem either worthy of inclusion in the Dura-Ace family, instead sidelining them as “non-series” components, dubbed 785 and 685. Now, the R9170 levers and rotors are officially part of the top-tier echelon.

As with the electronic transmissions, the R9170 and eTap HydroHC share cranks, cassettes and chains with their mechanical siblings.

Neither company has yet released their electronic/hydraulic groups for test. Stay tuned.

  • Shimano R9170 group – 2,389g – $3,137 / £N/A
  • SRAM Red eTap HydroHC group – NAg – $N/A / £N/A

Power meter comparison: Shimano FC-R9100-P vs Quarq

Regarding power meters, Shimano has been off the back. As a slew of companies cropped up with watt-measuring devices, Shimano sat silently. SRAM jumped into the game with the purchase of Quarq in 2011. In 2012, Shimano bought BikeFitting, a Dutch company with power-measurement technology.

This new Dura-Ace crank feautres strain gauges on both crank arms, plus a ‘brain’ inside the spider

For 2017, Shimano will have its first power meter, the FC-R9100-P. This new Dura-Ace crank features strain gauges on both crank arms, plus a ‘brain’ inside the spider. The meter can be updated via a Bluetooth connection, and recharged through a magnetic adapter that doesn’t require removing a cover.


For its part, SRAM’s Quarq comes in a variety of configurations. While Shimano and Campagnolo required riders to buy a third-party meter for power measurement, SRAM led the game with an integrated Quarq option as part of its Red offerings. Quarq measures power at the spider.