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Rotor2INPower Powermeter Crank Arms - MTB


Item # RTR003C

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  • Black, 170mm ($1,250.00)
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Item # RTR003C

2INPower Powermeter Crank Arms

The Rotor 2INPower Powermeter MTB Crank Arms features two sets of strain gauges measuring power independently in each leg with the high accuracy level of +/- one percent. Power information is then wirelessly transmitted via Bluetooth Smart or ANT+ to your preferred head unit or Rotor's smartphone app available for iPhone and Android devices. For these mountain bike-specific 2INPower Powermeter Crank Arms, you'll find the electronics and battery are neatly tucked inside the axle where they're safe from moisture ingress and harsh abuse out on the trail.

While the electronics are all spindle-bound, there's four strain gauges in the axle for left leg measurement and four in the right crank arm for the right leg measurement. Rotor claims this design negates the need to re-calibrate settings due to drastic temperature swings. And seeing they're laid out in opposition, the eight gauges work as internal correctives to each other to provide more points of input, help the system reduce drift, and eliminate the need to constantly zero by establishing a more comprehensive body of aggregate data.

As with other power meter cranksets, the 2INpower is equipped with an accelerometer to read cadence; unlike other meters, Rotor's design measures cadence over 500 times per pedal stroke. While the benefits of mapping minute changes in cadence over each leg's power production are immediately obvious to any data obsessive, the potential is magnified exponentially when paired with Rotor's Q-Ring system. It helps you chart the most efficient Q-Ring orientation possible to capitalize on the strengths of your pedal stroke while mitigating the weaknesses. The crank arms work just fine with traditional round rings, but adding Rotor's Q-Rings takes full advantage of the system's potential.

The 2INPower Powermeter MTB Crank works with Rotor's 30-millimeter Universal Bottom Bracket (UBB) design, making it compatible with nearly all standard frames on the market with the use of spacers (the only exception is it's not compatible with BB90). For chainring choices, you must run them with Rotor's direct-mount mountain bike rings, either their NoQ rings or Q-rings with a 110-millimeter bolt circle diameter, ranging from 26 to 34-tooth sizes for customizing your gearing range. The battery is fully contained and rechargeable via a magnetic connection in the proximal end of the crank arm. While it's recharging, Rotor provides a seamless data upload and management interface by partnering with TrainingPeaks.

  • Mountain bike powermeter cranks with +/-1% accuracy
  • Eight strain gauges increase accuracy, reduce need to zero
  • Independently measures left and right leg power output
  • Charts cadence information 500 times per pedal stroke
  • Electronics housed in spindle to keep out the elements
  • Compatible with Rotor's direct-mount NoQ and Q-rings
  • Charts maximum pedaling efficiency with Rotor Q-Rings
  • Bluetooth Smart and ANT+ for head units and smartphones

Tech Specs
Arm MaterialCNC-machined 7055 aluminum alloy
Arm Length165 mm, 170 mm, 175 mm
Bolt Circle Diameter110 mm
BB TypeBB30, Pressfit 30 (PF30), BSA, BB89, BB92
Spindle30 mm
Q Factor169.5 mm
Compatible ComponentsRotor direct-mount round and oval rings, 9/10/11-speed drivetrains
Recommended Usemountain biking
Manufacturer Warranty2 years

Actual Weight

Black, 170mm

Claimed Weight

Claimed weights are provided by the vendor.

Have questions? Chat with a Gearhead

1lb 8.5oz

Actual weights are measured in-house by the Competitive Cyclist team.

Have questions? Chat with a Gearhead

What do you think about this product?



Will this product fit my specialized epic hardtail which has a SRAM DUB BSA 73mm threaded bottom bracket? Also boost spacing.

Hi Brice, 2 INpower cranks use a 30 mm Universal Bottom Bracket (UBB) system and the BOOST standard in the MTB version that’s compatible with BB30, PF30, BBright, BSA30, ITA30, BB86,386 EVO, BB89, BB92 and BOOST frames. You would need to use one of Rotors UBB bottom brackets, like this one:

>Rating: 5

Consistent and Reliable

I've put it through the wringer

Power meters do not get any better than this. This power meter is awesome. It is easy to use, consistent, reliable, and durable. It even comes with a charger! No changing batteries here. It is easy to pair with any computer and calibrate. Then you're off riding. You don't even have to calibrate every time. This thing picks up more data points in your pedal stroke than any other option. It is dual sided and picks up your left/right balance. There is no question in your data feedback with this option. It will get it right every time and provide the data you need.


Are these Boost-compatible? I have a current SRAM Eagle 1x setup on a Yeti SB4.5 and want to know if this will work together.