Frequently asked questions


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What am I going to find in the INpower product box?

There are two possibilities when buying INpower.

When buying the complete set of left and right crank assemblies, you will find an installation and a User Software manual (User Software can be downloaded for free from ROTOR’s website), and a Training Peaks manual. Training Peaks has offered INpower customers a free premium account subscription to those who purchase INpower. Visit to obtain the maximum benefit from this new alliance.

If you only buy the left crank assembly, together with it you will find the same manuals mentioned previously, and a set of washer, bolt and self-extractor nut. These must be used to install the right crank assembly of your existing cranks with your new left INpower crank assembly. Never use another bolt or self-extractor nut to install INpower cranks.

Why is there bolt, nut and washer together with my INpower left-crank assembly if Ibought it separately?

The bolt and self-extractor nut from the non-power meter crancks are not compatible with the INpower axle. If you have purchased the left-crank assembly with the axle because you already have ROTOR cranks, you need to substitute the old bolt and self-extractor nut with the new washer,bolt and self-extractor nut included in the INpower package.

Read the user manual carefully to correctly install these INpower parts. If you have purchased the complete set of the left and right-crank assemblies, the self-extractor mechanism is already installed and you do not need to make any modifications.

Do not uninstall the self-extractor set once it has been successfully installed.

How do I know if my frame is compatible with the INpower axle?

INpower is equipped with the UBB30 axle system, which was introduced by ROTOR. UBB30 is a 30mm diameter axle which is compatible with almost all standard frames in the market (when used with the correct spacers).

ROTOR INpower can be installed on you bicycle even if your current cranks are 24 mm diameter.

UBB30 is compatible with the following standards: BB30 (68/73mm), PF30 (68/73 mm), BSA threaded, ITA threaded, BBright and BBright Direct Fit, BB86, BB386 EVO, BB89 and BB92.

The only frames not compatible with the UBB30 system are BB90 and BB95 (both for 24 mm diameter axle). These two standards use bearing that are directly pressed into the frame, without using any intermediate bottom bracket.

How does ambient temperature affect power measurement?

Ambient temperature does not positively or negatively affect how ROTOR INpower works. INpower gives accurate and stable power measurement no matter what changes in temperature occur during a ride (e.g. long climbs with higher temperatures at the beginning and lower temperatures at the end).

It is not necessary to calibrate INpower due to temperature changes. 

Can I disassemble my power meter?

The only parts that can be disassembled are those that are involved in installing and uninstalling both the cranks on the bicycle, and the battery and battery cap. Read the user manual carefully before handling the product. Never try to disassemble the plastic part at the end of the left crank and/or the electronics inside the axle.

Do not try to disassemble the mechanical elements assembled by the manufacturer, such as the axle with the left crank, the self-extractor system, or the spider with the chainrings on the right side.

How often should the battery be replaced?

ROTOR INpower uses a standard AA 1.5 V battery. The battery is not included in the original packaging.

Battery life is usually 300 hours for fully-charged, alkaline batteries from leading brands. When the battery is near the end of its life, the ROTOR INpower cranks will send a message to your ANT+ device that will warn you that you’ll need to change it soon.

You can see the battery status by connecting the crank to the ROTOR User Software running on your computer. The User Software can be downloaded for free from ROTOR’s website.

In order to connect the crank to the computer, a USB ANT+ stick is necessary. Contact your ROTOR retailer or local distributor to acquire one.

Read the user manual before opening the battery cap. Opening the battery cap is only recommended when it is necessary to change the battery or uninstall the cranks. Inadequate handling of the battery cap can damage the O-ring and the seal.

How do I replace the battery?

Read the user manual for a correct battery replacement.

The positive side must be facing outward.

The battery model and polarity are printed on the inside of the plastic cap.

Can I use rechargeable batteries?

Yes, you can use them if they are AA batteries with 1.5 V.

Battery life depends on the manufacturer and model. Rechargeable batteries usually have a lower life, which is reduced even further the more you recharge them.

My battery seems swollen or shows signs of corrosion.

Discard damaged batteries immediately. Using damaged batteries can damage the electronic parts inside the axle and void the warranty.

If I usually connect my INpower to the User Software running on the computer, is the battery life still 300 hours?

If fast mode is active (only possible with User Software), battery consumption is higher due to the higher frequency of data emission required by the Torque 360 graph.

Always disconnect the power meter when closing the program to make sure that fast mode is off.

How can I clean my INpower cranks? Are they waterproof?

INpower is waterproof. It has successfully passed level IPX7.

Nevertheless, do not clean your power meter with high pressure and avoid direct impact on the joints.

Do not use solvents or degreasers; they can damage some power meter elements.

Make sure that the O-ring is correctly placed in the cap after every battery replacement.

How can I update the firmware for my cranks? How often do I have to update the firmware?

ROTOR sometimes offers new versions of the firmware in order to improve previous versions.

The update process is wireless; to complete this you will need to download the User Software from the ROTOR website.

To connect the crank to the computer, a USB ANT+ stick is needed. Contact your ROTOR retailer or local distributor to acquire one.

What happens if there is an error while updating the firmware?

If any error occurs during the updating process, your cranks will keep functioning normally with the previously-installed firmware. If the update process begins and the program detects any problem, the process will restart a maximum of 5 times before cancelling the update.

It is recommended to place the USB ANT+ stick as close to the cranks as possible for better radio signal reception.

How do I calibrate/zero INpower?

Ride a few meters to activate the power sensor or apply force to the non-drive side crank to turn it on. Place the left (non-drive side) crank at a 6 o´clock vertical position.  Follow your ANT+™ device directions to find the calibration menu. Push “Calibrate” without any weight on your pedals. The calibration value should show “1000.” After you see 1000 appear on the screen slowly turn the crank counterclockwise two or three turns and place it in a 6 o’clock vertical position again. Push “Calibrate” again and record the offset value shown in the monitor. You can repeat the process if necessary to ensure numbers are in the same range.

How often do I need to calibrate my ROTOR INpower?

To assure accurate measurement, it is necessary to correctly calibrate the cranks. It is not necessary to calibrate INpower before every ride, but it must be calibrated when:

–        Power meter is installed in the bicycle

–        Pedals are installed or changed

–        Chainrings are installed, requiring the cranks to be disassembled.

Battery replacement does not require recalibration.

Calibrating a second time is recommended after 30 hours of riding.

Read the user manual carefully to successfully complete the calibration process.

Why do I have to calibrate twice?

The calibration process requires pressing the calibration button twice on your ANT+ device. This is necessary for calibrating force and angle.

It is very important that you follow the steps described in the user manual for correct calibration. This assures an accurate power measurement.

What are the calibration values?

ROTOR INpower also requires angle and force calibration. After the calibration button is pressed the first time, you must see a value of 1000 on your device’s screen. After the calibration button is pressed a second time, the screen’s value must be between +/-200. This second calibration value is specific to each power meter.

If I have doubts that I've correctly calibrated my power meter.

Read the user manual carefully and calibrate the cranks as explained.

If you have doubts about correct calibration, repeat the entire calibration process and compare the two values obtained in the last step of each process. This value must stay the same (variations of 1 or 2 units are normal). You can calibrate your cranks using either your ANT+ device or the User Software, which can be downloaded for free from ROTOR’s website.

How often are the power values shown?

ROTOR INpower becomes active after pedaling starts. Sampling frequency is 200 Hz, which means that force data are measured 200 times per second.

The data sent to the ANT+ device are from the last completed pedal rotation. How long a single pedal rotation lasts depends on the cadence of the cyclist, for example, if the cyclist pedals at 90 rpm then the rotation lasts 0.67 seconds.

The power measurement of a rotation is sent according to ANT+ protocol: 4 times per second. How data are recorded and accumulated depends on the ANT+ device. Devices usually offer the option to record data once per second, or to record data in “Smart” mode.

Which data related to power are provided by INpower?

INpower processes and provides values of: Power, Cadence, Torque Effectiveness and Pedal Smoothness.

A balance value is also shown, which is set by default as 50%-50% (assuming a perfectly-balanced cyclist).

INpower also calculates and shows additional information that can only be viewed through the User Software: Torque 360 and OCA (Optimum Chainring Angle).

How can I see Torque Effectiveness and Pedal Smoothness data?

Both metrics are accessible by ANT+-compatible device manufacturers and it is their decision whether to show them or not on their devices.

Most ANT+-compatible devices already feature these metrics’ recordings and visualizations.

How can I see the Torque 360 graph and my OCA value?

Currently these data are only accessible using the User Software that can be downloaded for free from ROTOR’s website. Once you have successfully downloaded and installed the software, you will need a USB ANT+ stick to receive data sent by INpower (stick not included, contact your ROTOR retailer or local distributor to obtain one).

Visit for further information, to download the ROTOR User Software, and to learn more about Torque 360 and OCA.

Is it necessary to install a cadence sensor on my bicycle?

Your ROTOR INpower cranks have a cadence sensor incorporated in the axle and do not need an external sensor.

It is recommended to uninstall any cadence sensor from your bicycle to avoid interferences.

How do I pair INpower with my ANT+™ cycling computer?

Your “SENSOR ID” can be found on the inner side of the non-drive side crank. It is the 5-digit number shown next to the barcode on the crank or the 5-digit number shown on the axle´s label. Find your “sensor details” in your computer (note: make sure power sensor is “enabled”).  Manually enter the 5-digits of your sensor ID. Activate your crank by applying force to the non-drive side crank (ride a few meters or push down on the crank). Your computer should automatically find your power sensor. You do not need to hit the “search” function.

My ANT+ device does not detect the power sensor.

First of all make sure that your ANT+ device has the power sensor option active, then pair the power meter with the device.

Read the user manual to correctly pair your power meter with your ANT+ device. The first step is to activate the power meter by riding a few meters (a 2.5 kg force must be applied on the left pedal). Take into account that after two minutes of inactivity, INpower enters hibernation mode to reduce battery consumption.

My INpower does not activate even after applying force to the pedals.

Check to see if the battery is correctly installed with the positive side facing outward. Check to see if the battery is charged.

If you still have problems, uninstall the drive-side crank assembly and look at the inside of the axle on the right side. It isn’t necessary to uninstall the axle from the bicycle. When installing a new battery, you must see the yellow LED light. If this does not occur, contact your ROTOR retailer or local distributor for more information.

My power meter connects with the computer but not with the ANT+ device.

Follow the instructions detailed in the user manual for correct pairing with your ANT+ device. If the device is correctly paired and active and connects with the computer (with the User Software) without any problem but does not connect to the ANT+ device on your bicycle, it is possible that the cranks are still in fast mode.

To avoid this, always disconnect your power meter from the User Software before closing the program.

If fast mode cannot be disconnected, remove battery and wait a couple minutes before replacing it. During these two minutes the crank is still active even without the battery in order to avoid losing data in case of involuntary disconnections.

How do I get spare parts?

Please contact your ROTOR retailer or local distributor.

Do not try to disassemble your power meter except to install it and/or replace the battery. Improper handling will void the warranty.

Who do I contact for warranty issues?

Please contact your ROTOR retailer or local distributor. ROTOR provides two years of warranty for all its products in compliance with European law. 

What kind of support can I expect if I need assistance with my INpower?

You will find all the necessary information about installation and how to use INpower by visiting:

If you have any questions, suggestions or technical service requests, contact your retailer or local distributor. You can also contact ROTOR technical service directly by emailing:

[email protected]

What does it mean to train with power?

Visit for a better understanding of how training with power works.

ROTOR recommends subscribing to TrainingPeaks to obtain the maximum benefit of the data provided by your power meter.

What software can I use to analyze my data?


How do I decide which INpower to buy if I already have a ROTOR crankset?

One of the many advantages of the INpower power meter is its compatibility with every ROTOR crankset with 30 mm axles (FLOW, 3D+ and 3D30 road cranks; REX1 and REX2 MTB cranks; it is also compatible with the specific 3D+ and 3D30 models for cyclocross).

If you are already using a ROTOR crankset, you have the opportunity to purchase the non-drive-side INpower assembly for your current model (if it is not prior to 2013). To complete the installation, you may use the drive-side crank assembly that you already have.

Make sure the length of the new INpower crank and your current crank are the same in order to guarantee full compatibility.

WARNING: you must use the self-extractor set of washer, bolt and nut included with your left INpower assembly. If another bolt is used it will damage the electronics located inside the spindle. If this happens, the warranty is no longer valid. Follow the instructions on the user manual to correctly install the INpower drive-side crank assembly.

How often do I need to calibrate my ROTOR 2INpower?

To assure accurate measurement, it is necessary to correctly calibrate the cranks. It is not necessary to calibrate your 2INpower before every ride, but it must be calibrated when:

-Power meter is installed on the bicycle

-Pedals are installed or changed

-Chainrings are installed, requiring the cranks to be disassembled.

Calibration is not required after charging the battery.

Calibrating a second time is recommended after 30 hours of riding.

Read the user manual carefully to successfully complete the calibration process.

ROTOR Power vs INpower

ROTOR Power mide ambas piernas por separado utilizando medidores en cada biela. ROTOR INpower realiza la medida sobre la pierna izquierda. La potencia que se muestra es el resultado de la extrapolación (funcionamiento por defecto para multiplicar por dos la potencia medida en la pierna izquierda). Además de las nuevas métricas para el análisis del pedaleo introducidas por ROTOR Power (efectividad del par y suavidad del pedaleo) ROTOR INpower ofrece información adicional, cómo el gráfico 360º y el OCA

ROTOR Power vs INpower?

ROTOR Power measures both legs separately using gauges placed in each crank. ROTOR INpower measures in the spindle power generated by the left leg. The power value that’s shown is the result of extrapolation (default operation to multiply by two power measured in the left leg). In addition to the new metrics for pedal analysis introduced by ROTOR Power: Torque Effectiveness and Pedal Smoothness, ROTOR INpower offers additional information, such as the Torque 360 graph and the OCA (Optimum Chainring Angle) value.

What ANT devices is ROTOR INpower compatible with?

They are listed in the ANT+ directory: