4iiii PRECISION 3+ Shimano Ultegra R8100 Power Meter

4iiii PRECISION 3+ Shimano Ultegra R8100 Power Meter

Introducing the all new 4iiii PRECISION 3+ Shimano Ultegra R8100 Power Meter. 4iiii has combined their patent pending 3-D tri-axial strain gauge technology, measured at +/- 1.0% accuracy, with Shimano’s 12-speed Ultegra R8100 groupset. The result is one of the lightest, most affordable and most accurate direct force power meters available.

The PRECISION determines your total power based on the force that is generated by your left leg. This left-only design allows for a power meter that is lightweight and easy to install. Specifically, the power meter adds only 9 grams to your crank arm and is installed in about 10 minutes. In addition, the PRECISION is compatible with both ANT+ and Bluetooth SMART devices. This means you can use it with your favorite bicycle computer, watch or smart phone.

Key Product Details

Compatibility:

This power meter is compatible with Shimano R8100 cranksets. It can also be installed on other Shimano road cranksets, as long as they use Shimano’s Hollowtech II interface. See Compatibility tab for more information.

Power Measurement:

This 4iiii power meter measures left leg power and doubles the value to account for both legs (assumes both legs are generating the same force).

New 4iiii R8100 PRECISION 3+!

The all new 4iiii R8100 PRECISION 3+ power meter features the following improvements over the version 2:

• Apple Find My which allows you to always know where your bike is!
• 800 hours of battery life – the longest coin cell battery life in a power meter on the market!
• Sleeker, slimmer profile making most incompatibility issues a thing of the past.
• Stronger antenna for even better connectivity.
• Indicator light for battery life, successful zero-offset and when the unit has been turned on.

Key Features:

Affordable, accurate to within +/- 1.0%, lightweight at only 9 grams of added weight, 800 hours of battery life, CR2032 user-replaceable battery, ANT+ and Bluetooth compatible, easy to install, 3-year warranty. See Specs tab for more information.

Advice From Our Staff:

4iiii left side crank arms are some of our best-selling units. They work with most Shimano cranksets, are affordable and easy to install. The one consideration is they only measure left leg power compared to some other power meters that measure power from both legs (those versions usually cost more however).

Options For This Power Meter

Crank arm lengths: 165 mm | 170 mm | 172.5 mm | 175 mm

Other Versions to Consider

Dual-Sided R8100 Crankset: We also sell the 4iiii PRECISION PRO Shimano Ultegra R1000 Dual-Sided Crankset which is a complete crankset. It is more expensive, however it measures power from both legs.