Shimano 105 Gen 3 L Power Meter Crank Arm

Now that you're looking to take your riding to the next level, you want to add a power meter to your setup to maximize your training but you have a couple of reservations. You don't want to waste your existing crankset, and you don’t want it to cost a fortune. Thanks to Stages Cycling and its Shimano 105 L Gen 3 Power Meter Crank Arm, you can simply add on a non-driveside crankarm letting you maintain the aesthetic and precision shifting rings while adding accurate power measurement to your steed.

This non-drive side crank arm is exactly the same as the standard 105 crank arm you currently have with a Stages power meter affixed to its inner surface. Tucked inside this little pod, strain gauges and an updated Gen 3 accelerometer measure torsional force and rotation speed to calculate power and deliver this data to your head unit via updated Bluetooth LE or ANT+ radios with a 6-time improvement in transmission strength. These measurements come with a claimed accuracy of +/- 1.5%, which is very much in-line with the best power meters on the market.

The power meter also incorporates Stage's Active Temperature Compensation (ATC), which compensates for the natural expansion and contraction of the strain gauges by adjusting the readings depending on external temperature. ATC accounts for those temperature changes without requiring you to stop pedaling in order to zero the system. Overall, the power meter adds less than 15g to the crank, which is a tiny tradeoff for its ability to capture power information as it transfers from the pedals into the drivetrain. A simple coin-cell battery and wireless firmware downloads make this power meter easy to service and keep up to date.

• A 105 left crankarm with power measuring capability
• Measures power with an impressive +/-1.5% accuracy
• Active Temperature Compensation accommodates changing temperatures
• Updated accelerator measures cadence
• Improved wireless communication boosts the signal strength
• Pairs with Stages Power App for firmware updates and zero resets
• 200+ hour battery life with easily-changeable CR2032 coin-cell battery
• Stages Cycling brings power data into an affordable price range