Multi-Buy Savings!
Code: PML100-S10
4iiii Precision Ultegra R8000 Left Arm Powermeter
Accurate measurement of cycling effort is vital for anyone who takes cycling seriously. PRECISION powermeters provide industry leading accuracy, together with reliable cadence data. PRECISION 3D technology is capable of measuring tri-axial strain on the crank arm, ensuring the accuracy of the measurement. Designed to work flawlessly with Bluetooth and Ant+ head units, PRECISION powermeters offer an accurate, lightweight, durable and affordable method of measuring rider power.    
 
PRECISION power meters are installed on a new Shimano left crank arm (105, Ultegra, or Dura-Ace). These crank arms will fit bottom brackets using the Hollowtech ii format.
 
Features
  • 3D powermeter technology (patent pending) measures tri-axial strain on your crank arm
  • Accurate, consistent data
  • Lightweight, compact design
  • Battery status indicator via 4iiii app
  • Compatible with ANT+, Bluetooth Smart head units, smartphones, and other 4iiii products
  • User-friendly app and configurable rider compensation scale factor
  • Easy setup and maintenance
 
Specifications
  • Weight: 9 grams
  • Data accuracy: +/- 1% error margin
  • Battery life: 100+ riding hours on 2032 coin cell battery
 
Note: Check your frame clearance before you order by downloading and printing the compatibility guide Click Here
I've had the 105 version for a year, bought this one for a new bike. Functionally the Ultegra is identical. The only problems I've found over 1000's of km's is an occasional failure to reconnect after a coffee stop on a club run and a tendancy for the battery terminal to flatten out and cut out the unit. These two issues might be connected. The battery issue is easily fixed by pulling the terminal up witha slim blade. No problems with water getting in, I take no precautions washing down, it gets hit with detergent, water and degreaser regularly and has no problems. Paired with an Elemnt you get a battery warning when its low which is useful. The odd glitch wasn't enough of an issue to stop me buying a second.