Which Power Meter Fits A Shimano Crankset?

Founder, Mr. Mamil
Shimano Dura Ace R9200 Crankset
Shimano Dura-Ace R9200 Crankset

Planning to add a power meter to your Shimano crankset?

There are four options for you to consider;

  • Left-sided
  • Spider-based
  • Crankset-based
  • Pedal-based

In this article, we’ll explore the four options in detail.

Left-sided power meters

Stages for Shimano Dura Ace R9200
Stages Power Left for Shimano Dura-Ace R9200

4iiii and Stages manufacture left-sided power meters that fit onto a Shimano crankarm;

  • Stages Power Left
  • 4iiii Precision 3
  • 4iiii Precision

You can purchase the left crankarm with the built-in power meter. The unit weighs 9g for 4iiii and 15g for Stages.

With 4iiii, you can also send the existing left crankarm to them to fit the power meter unit.

They’re available in 165, 170, 172.5, or 175mm and for the Shimano 105, Ultegra, and Dura-Ace range, as depicted by the table below.

Crankset model4iiiiStages
Shimano 105 R7000YesYes
Shimano Ultegra R8000YesYes
Shimano Ultegra R8100NoYes
Shimano Dura-Ace R9000NoYes
Shimano Dura-Ace R9100YesYes
Shimano Dura-Ace R9200NoYes
4iiii and Stages left-sided power meter availability
More reading : 4iiii Precision 3 vs Precision Power Meter Comparison

Crankset-based power meters

4iiii Precision Pro for Shimano Dura Ace R9100
4iiii Precision Pro for Shimano Dura-Ace R9100

Besides left-sided power meters, 4iiii and Stages also have crankset-based (dual-sided) power meters.

  • Stages Power LR
  • 4iiii Precision Pro

There will be two power meter units, one each on the left and right crankarms. They’re available for these cranksets;

  • Shimano 105 R7000
  • Shimano Ultegra R8000
  • Shimano Dura-Ace R9100

Spider-based power meters

Power2max NGeco for Shimano
Power2max NGeco for Shimano Chainrings

For spider-based power meters, there are two options from Power2max.

  • Power2max NG Road, the top-of-the-line model with ±1% accuracy, rechargeable battery, and advanced power metrics.
  • Power2max NGeco Road, a mid-range model with ±2% accuracy and uses a CR2450 coin battery.

The Power2max will work the existing 4-bolt Shimano chainrings (110-4S), but will require a new crankarm from Rotor with 24mm spindle (ALDHU 24). The crankarms are bundled with the power meter.

More reading : Power2max NG Road vs NGeco Road Power Meters

Pedal-based power meters

For pedal-based power meters, you can choose between;

  • Garmin Rally RS (Shimano) or RK (Look)
  • SRM Exakt
  • Favero Assioma

Pedal-based power meters are the easiest to install by just swapping out the existing pedals.

ComparisonGarmin RallySRM ExaktFavero Assioma DuoFavero Assioma Duo-Shi
Weight (pair)320g to 326g310g303gvaries**
Battery Life120 hours30 hours50 hours50 hours
Cleat typeShimano SPD-SLLook KeoLook KeoShimano SPD-SL
Pedal stack13.5mm10.5mm10.5mmvaries***
Warranty1 year2 years2 years2 years
Price$1100 (dual)
$650 (left)
$1300 (dual)
$750 (left)
$759 (dual)
$495 (left)
$659 (dual)
Comparison between Garmin Rally, SRM Exakt, and Favero Assioma power meters

Notes :

  • * Weight – Garmin Rally RS200 (320g), Rally RK200 (326g), Rally RS100 (160g), Rally RK100 (163g)
  • ** Weight depends on the Shimano pedal body used. The spindles weigh 198g/pair and 314g/pair when used with a Shimano R8000 pedal body.
  • *** Pedal stack depends on the Shimano pedal body used.
  • **** Q-factor – 65mm (Shimano R8000/R6800), 64mm (R550/R540)

Garmin Rally

Garmin Rally RS200 Power Meter
Garmin Rally RS200 Power Meter

The Garmin Rally is the latest power meter by Garmin, with four models.

  • RS200, dual-sided, Shimano SPD-SL cleats
  • RS100, left-sided, Shimano SPD-SL cleats
  • RK200, dual-sided, Look Keo cleats
  • RK100, left-sided, Look Keo cleats
More reading : Garmin Rally RS200 Review

SRM Exakt

SRM Exakt Power Meter
SRM Exakt Power Meter

The SRM Exakt is an SRM power meter built into a Look Keo pedal. It’s available in single-sided (left) or dual-sided options.

Favero Assioma

Favero Assioma Duo Power Meter
Favero Assioma Duo Power Meter

The Favero Assioma is available in three variants;

  • Assioma Duo, dual-sided, Look Keo cleats
  • Assioma Uno, left-sided, Look Keo cleats
  • Assioma Duo-Shi, dual-sided, Shimano SPD-SL cleats

The Favero Asisoma Duo-Shi is sold with pedal spindles only and without a pedal body. You’ll need to use an existing Shimano pedal and install it on the Favero Assioma Duo-Shi.

The compatible pedal bodies are the Shimano PD-R8000, PD-R7000, PD-6800, PD-R550, and PD-R540.

Alex Lee at Mr.Mamil

Alex Lee is the founder and editor-at-large of Mr. Mamil. Coming from a professional engineering background, he breaks down technical cycling nuances into an easy-to-understand and digestible format here.

He has been riding road bikes actively for the past 12 years and started racing competitively in the senior category during the summer recently.