Train and race with accurate, dual-sided power data without giving up the shifting performance you expect from Ultegra. The FC-R8100-P brings Shimano's dual-sided power meter to a HOLLOWTECH II road crankset, so you can measure left and right leg output independently while enjoying crisp 12-speed front shifting from the HOLLOWGLIDE chainrings.

Highlights

  • Dual-sided power measurement reads each leg independently for true left/right balance
  • Accurate within 2.0% across the calibration range for trustworthy training numbers
  • Integrated, waterproof, rechargeable Li-ion battery delivers up to 300+ hours of ride time
  • Connects via ANT+ and Bluetooth LE to head units, apps and trainers
  • HOLLOWGLIDE chainrings keep weight low and front shifting fast and precise
  • Proven HOLLOWTECH II construction for stiff, efficient power transfer

Accurate, dual-sided data

Strain gauges bonded to both crank arms measure your true left and right leg output, so you see real pedalling balance rather than an estimate doubled from one side. Measurement stays accurate within 2.0% across the calibration range, with quick zero-offset calibration before you ride. Force vector data helps you analyse and refine your pedal stroke.

Built to ride, not to fuss over

The integrated, waterproof, rechargeable Li-ion battery gives up to 300+ hours of ride time between charges, so there are no coin cells to swap. Power broadcasts over both ANT+ and Bluetooth LE, letting you record on a head unit while connecting to training apps at the same time.

Ultegra shifting performance

This is a full HOLLOWTECH II crankset, not just a spider. The HOLLOWGLIDE chainrings cut weight while holding their shape under load for quick, reliable front shifts, and the hollow-forged arms deliver the stiffness that makes power transfer feel direct.

Compatibility & fit

Designed for 2x12-speed Shimano road drivetrains. This crankset is the 170 mm, 52-36T configuration with a 110 mm asymmetric 4-arm bolt circle diameter (BCD) and a 44.5 mm chainline. It uses the HOLLOWTECH II 24 mm steel axle and requires a compatible HOLLOWTECH II road bottom bracket (sold separately) to suit your frame's shell. The TL-FC40 preload tool is included.

Shimano components are covered by a manufacturer's warranty against defects in materials and workmanship. Electronic power meter components, including the integrated battery, are covered for the period specified in Shimano's warranty terms applicable at the time of purchase. The warranty does not cover normal wear (such as chainring tooth wear), crash damage, improper installation, or damage from unauthorised modification.

For warranty support, return the item to Tune Cycles and we'll manage the claim for you.

This warranty is in addition to your rights under the Australian Consumer Law. Our goods come with guarantees that cannot be excluded under the Australian Consumer Law. You are entitled to a replacement or refund for a major failure and compensation for any other reasonably foreseeable loss or damage. You are also entitled to have the goods repaired or replaced if the goods fail to be of acceptable quality and the failure does not amount to a major failure.

  • Dual-sided power meter measuring left and right leg output independently
  • Accurate within 2.0% across the calibration range with quick zero-offset calibration
  • Force vector data to analyse and improve pedal stroke efficiency
  • Integrated, waterproof, rechargeable Li-ion battery, up to 300+ hours ride time
  • ANT+ and Bluetooth LE connectivity
  • HOLLOWTECH II hollow-forged crank arms for stiff, efficient power transfer
  • HOLLOWGLIDE chainrings for low weight and fast, precise front shifting
  • 2x12-speed road, 52-36T, 170 mm arm length
  • 110 mm asymmetric 4-arm BCD, 44.5 mm chainline
  • TL-FC40 preload tool included
Part numberFC-R8100-P
SeriesShimano Ultegra R8100
TypeDual-sided power meter crankset (HOLLOWTECH II)
Speeds2x12-speed road
Chainrings52-36T (HOLLOWGLIDE)
Crank arm length170 mm
BCD110 mm, asymmetric 4-arm
Chainline44.5 mm
Axle / interfaceHOLLOWTECH II, 24 mm steel axle
MeasurementDual-sided, accurate within 2.0%
BatteryIntegrated, waterproof, rechargeable Li-ion; up to 300+ hours ride time
ConnectivityANT+ and Bluetooth LE
IncludedTL-FC40 preload tool
SKU SHM-IFCR8100PCX26D
Barcode # 4550170172831
Brand Shimano

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