Rotor has expanded its power meter range with the launch of INpower, a power meter housed inside the bottom bracket axle. Prices start from £499 for a left arm only option, while a complete INpower 3D+ crankset costs £699, but that price doesn't include the chainrings. INpower uses a single AA battery offering a claimed 300 hour battery life.
INpower features a bottom bracket axle integrated to a non-driveside crank arm. It measures power spindle power generated by the left leg, and the extrapolats that to provide the power value displayed on a compatible device. The power meter adds only a little weight to the crankset, the lightest left arm only option is a claimed 325 grams.
If you already own a Rotor chainset you can just buy the left crank arm, as it’s compatible with any current Rotor UBB30 crankset with a 30mm axle. Or you can buy the complete crankset (not including chainrings), which is compatible with most modern road frames. Rotor is also offering a version for cyclo-cross and mountain bikes.
Rotor says the INpower “achieves cleaner data transfer and greater accuracy via ANT+™ protocol without succumbing to interruptions and temperature fluctuations” and also cites another advantage being that the power meter is protected from shock, crashes and outside contaminants.
Rotor has developed some tools to help you get the most out of the power meter. Torque 360 and Optimum Chainring Angle (OCA) together allow pedal analysis enabling the pedal stroke to be assessed for efficiency, so you can see variations in the pedal stroke. It’s also designed to help anyone using Rotor’s non-round Q-Rings to orient them in the optimum position setting. Other tools include Torque Effectiveness and Pedal Smoothness to determine total torque versus positive torque and average power versus maximum power respectively.
"We wanted to create a power meter that overcame current trends in power meter technology and could be transferred to other disciplines," said Pablo Carrasco, head of research and development at ROTOR and INpower's inventor. "At the same time we wanted to leverage the benefits of Q-Rings and build a sophisticated power meter that's fairly simple to use compared with other power meters out there."
Rotor has been developing the INpower power meter for some time, and has used its partnership with the Merida-Lampre team to gain valuable feedback in race situations.
"I have been testing and providing constant feedback for INpower's development since the season's start," said Rui Costa. "and due to the product's significant benefits, I've decided to use it throughout 2015, including in the Tour de France."
With the launch of INpower, Rotor’s existing Power and Power LT power meters will still be sold, with prices reduced. ROTOR Power will now be offered for €1,299 (previously €1,699) or US $1,559 (from $2,400) and POWER LT has been lowered to €899 (from €999) and US $1,079 (from $1,490). We don’t have UK prices at this stage.
Here are the prices for the INpower options:
INpower 3D+ crankset £699 RRP
INpower 3D+ left arm only £549 RRP
INpower Flow left arm only £599 RRP
INpower 3D30 left arm only £499 RRP
David has worked on the road.cc tech team since July 2012. Previously he was editor of Bikemagic.com and before that staff writer at RCUK. He's a seasoned cyclist of all disciplines, from road to mountain biking, touring to cyclo-cross, he only wishes he had time to ride them all. He's mildly competitive, though he'll never admit it, and is a frequent road racer but is too lazy to do really well. He currently resides in the Cotswolds.