The Most In-Demand Bikes? We Just Got Them In. Shop Now
This carousel displays a list of buttons that updates the main product image when a button is clicked
  • Options
  • Detail Images

4iiiiShimano Ultegra R8000 Precision Left-Side Power Meter


Item # FII0003

Select options
  • Cancel
  • Select options
  • Grey, 165mm ($349.99)
  • Grey, 170mm ($349.99)
  • Grey, 175mm ($349.99)
Add Protect+ Powered by Extend™
  • 100% Guaranteed Returns
  • Free Shipping on orders over $50

Item # FII0003

Shimano Ultegra R8000 Precision Left-Side Power Meter

You're a "numbers guy." It began in high school when your stats teacher handed out assignments, and continued into adulthood when your boss asked you to review the annual report. Even when you hop in the saddle to train, your mind is driven onward by the data that surrounds you. And that's why you ride with the 4iii Shimano Ultegra R8000 Precision Left-Side Power Meter — so you can push your limits knowing data from every pedal stroke is measured for optimal performance. And all you had to do was install the Precision power meter crank arm to collect tangible and reliable numbers on your quest to improve your ride.

The secret behind this crank arm is the 4iii power meter pod affixed to the side of the arm, which takes what was originally a standard Ultegra R8000 crank arm to the next level with readings accurate to +/− 1.0%. The coincel battery offers 100 hours of life, giving you plenty of time to gather and scrutinize data for rides to come before a recharge is required.

For those that obsess over every ounce, the Precision is one of the lightest power meters on the market, adding only 9 grams to the crank arm in exchange for precise data that only a power meter can provide. When the time comes to look over the facts and figures, simply connect the Precision to the 4iii app on your phone via ANT+ or Bluetooth SMART for information at your fingertips.
  • Hollowtech II left side crank arm with built-in 4iii power meter
  • +/- 1.0% accuracy lets you collect training data with confidence
  • Accelerometer with gyroscope offers detailed cadence readings
  • 9g design is one of lightest crank arm-based meters on the market
  • 100 hours of battery life via replaceable CR2032 battery
  • Pair to the 4iii app with ANT+ and Bluetooth SMART to transfer data

Tech Specs
CompatibilityHollowtech II
FeaturesDual-Channel ANT+, Bluetooth Smart,
Accuracy (+/-)1%
Batterystandard CR2032 coin cell battery
Operating Time100+ hours
Manufacturer Warranty3 years
Activityroad cycling

Actual Weight

Grey, 165mm
Grey, 170mm
Grey, 175mm

Claimed Weight

Claimed weights are provided by the vendor.

Have questions? Chat with a Gearhead


Actual weights are measured in-house by the Competitive Cyclist team.

Have questions? Chat with a Gearhead

What do you think about this product?


>Rating: 5

Accurate, Reliable, Would buy again

I've put it through the wringer
True to size
Size Bought

Took a gamble after reading some reliability complaints with other manufacturer's left sided power meters. Was glad I did. Have nothing but positive feedback on this 4iii meter. It's been rock solid, accurate, reliable with good battery life for over a thousand miles. Purchased the left side through Competitive Cyclist. Liked it so much decided to purchase the right side upgrade to complete dual sided metering (send your own crank arm) direct from 4iii. They sent the shipping box and had a very easy guided process and were very communicative throughout the whole transaction. Highly recommended!


Will this connect to the Wahoo Element by ANT+?

did u get an answer for this?