The ROTOR 2INpower DM is ROTOR’s latest axle-based power offering. Unlike the previous generation INpower, the 2INpower DM features independent left/right power measurement. ROTOR has added two additional sets of strain gauges to the right crank arm that measure right leg power. Four strain gauges located in the crank axle measure the left leg’s power output (as is the case with the previous INpower version). The ROTOR 2INpower has Bluetooth SMART functionality, a built-in rechargeable battery and comes with a bolt circle diameter (BCD) of 110 mm.
Installation of the 2INpower is pretty straightforward assuming you have insured compatibility with your current bike frame. The 2INpower is equipped with the UBB30 axle system, which was introduced by ROTOR. UBB30 axle is a 30 mm axle compatible with almost all standard frames in the market (when used with the correct spacers). ROTOR 2INpower can be installed on your bicycle even if your current cranks are 24 mm diameter. UBB30 is compatible with the following road standards: BB30, PF30, BSA threaded, BBright and BBright Direct Fit, BB86 and BB386 EVO. The only frames not compatible with the UBB30 system are the BB90 frames (for 24 mm axle). This standard uses bearings that are directly pressed into the frame, without using any intermediate bottom bracket.
The weight of the ROTOR 2INpower crankset is 645 grams in a 172.5 mm crank arm configuration. When considering weight, be sure to focus on added weight by taking into account the weight of the component(s) you are replacing. So in this example, if your existing crankset weighs 500 grams for example, you are only adding 145 grams to your bike by installing the 2INpower.
Left/Right Power Measurement
With 2 separate sets of strain gauges, the ROTOR 2INpower is able to measure both left and right leg power data independently. In addition, the 2INpower offers metrics for pedal analysis and monitoring such as TORQUE 360 and OCA (Optimum Chainring Angle).
The ROTOR 2INpower uses a rechargeable Li-ion battery.
The power meter will last for approximately 250 hours on a full charge. At 30 hours remaining, the 2INpower will show a “low battery” message and recharging is recommended.
Difficulty to Change
This is not applicable as the rechargeable Li-ion battery never needs to be replaced.
The ROTOR 2INpower transmits data via both the ANT+ and Bluetooth SMART wireless protocols. This allows you to use the power meter with any cycling computer, smartphone or tablet.
The 2INpower is accurate to within +/-1.5%. Most direct force power meters claim anywhere from +/-2% to +/-1%, so the 2INpower is right in line in terms of accuracy.
The 2INpower utilizes an accelerometer to measure cadence. The advantage to an accelerometer is that you don’t have to worry about gluing a magnet to your bike (the other way power meters detect cadence is with a magnet and reed switch).
As soon as you start riding, or apply any force to the non-drive side crank, the 2INpower will wake up. To calibrate, place the left crank at a 6 o´clock vertical position and without any weight on the pedals, perform a calibration using your head unit. 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. Calibrate once 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.
The 2INpower does not need to be calibrated before every ride, but rather after installing the power meter or changing any drivetrain componentry (pedals, chainrings, etc.). After the initial calibration, it is recommended you calibrate a second time after 30 hours of riding.
ROTOR provides two years of warranty for all its products.
ROTOR is known for their oval shaped Q-Rings so it was critical that their power meter be Q-Ring compatible. To this end, 2INpower features TORQUE 360 and Optimum Chainring Angle (OCA) pedal analysis, which helps cyclists assess force variations in their pedal stroke. TORQUE 360 and OCA values enable cyclists to orient their Q-Rings around their distinct pedaling characteristics in order to take advantage of their most productive zone. Note that since the 2INpower cranks have the same BCD as standard cranks, you can also use them with any compatible round chainrings. Being able to run oval shaped rings is a distinct feature of the ROTOR 2INpower. In fact, other than ROTOR, only PowerTap’s hub-based power meter has been proven to support oval rings.
You can choose the purchase the 2INpower with the MAS spider instead of the regular, 5-bolt spider. MAS stands for Micro Adjust Spider. The ROTOR MAS spider allows you to fine-tune your Q-Ring position to better suit your needs and pedaling style. ROTOR calls this the Optimum Chainring Position (OCP).
For example, using a standard spider and ROTOR Q-Ring, you typically have approximately 5 degrees of adjustment. The MAS spider has additional bolt hole options, effectively giving you half positions or approximately 2.5 degrees of adjustment.
In addition, there is no additional weight penalty when using the MAS spider.