6 Power Meters Reviewed

We put a range of the latest power meters to the test.

Power meters, unlike finicky indicators like perceived effort and heart rate, are an absolute measure to gauge fitness and effort, thus they’ve become required equipment for serious riders. Triathletes, who are notoriously particular about their training, are ideal candidates for these powerful training and racing tools.

The two main barriers to entry for power meters are price—often still in the multiple thousands—and the ability to switch a device between bikes. Keeping that in mind, we tested some less expensive options and/or those more easily transferable between bikes, for numerous factors: ease of installation and use, weight, clutter, and overall power measurement accuracy and consistency. Here’s what we found.

Pioneer Power Meter Cranksets

$1,950, Dura-Ace ($1,550, Ultegra), Pioneerelectronics.com

How it works:
Strain gauges get tucked discreetly into the spider and inner side of the left crank arm for dual-pedal data. The ANT+ crank-based meter comes pre-installed on either Shimano Dura-Ace or Ultegra crank sets and is swappable to any road or tri bike with a compatible drivetrain. Retro-fit kits are available through dealers for existing cranks ($1,300 total). It measures force and torque 12 times per rotation on both sides to provide fully comprehensive power and efficiency analysis. Claimed accuracy is
+/-2 percent.

Best for:
Serious age-groupers or pros seeking the most detailed analysis of power and pedaling data. Users get highly accurate real-time measurements, and can see pedal rotation efficiency comparisons to adjust race-day pedaling or dial efforts to maximize efficiency.

The good:
– Similar accuracy, consistency and comprehensive data as much more expensive crankset units
– Only adds 64 grams, which is outstanding for a top-end power meter
– Huge improvements over zip-tie install of original

The bad:
– Less data and functionality with third-party devices
– A bit tricky to switch to ANT+ mode for use with other devices
– Only two options; no SRAM or Campagnolo compatibility

Pair with:
Pioneer SGX SA9000—ANT+, outstanding touchscreen and display, extremely detailed data with vector graphics and charts

RELATED: How To Use A Power Meter In A Race

Stages Dura-Ace 9000

$900 (Shimano Ultegra, $800; SRAM X9, $700), Stagescycling.com

How it works:
It’s a crank-based, strain-gauge system for most bike types, with ANT+ and Bluetooth Smart compatibility. A minimalist design—the lightest in our test—and simple installation on almost any type of bike make this a go-to meter for multi-discipline riders (it’s easily transferred to compatible cranksets). Plus Stages says its active temperature compensation means fewer calibrations in changing temps. Claimed accuracy is +/-2 percent.

Best for:
Serious racers with one bike or multiple with the same crankset, especially if price is an issue. It’s the best choice in the group for mountain or cyclocross bikes. There’s only one-sided measurement though, so not the best choice if looking to dial a more symmetrical or rounder pedal stroke.

The good:
– Excellent accuracy for the price; Stages claims even higher accuracy at higher wattage
– Only about 15 grams for extra pod, and no clutter
– ANT+ and Bluetooth compatibility

The bad:
– Doesn’t work with some newer Bluetooth devices (like the Polar V800), but updates should fix this soon
– No dual-pedal data for pedal stroke analysis

Pair with:
Garmin 920XT: ANT+, multi-sport functionality, tons of data options, turn-by-turn navigation

RELATED: Is The Affordable Power Meter Finally Here?

Polar Keo Power

$1,950 ($1,150 for single), Polar.com

How it works:
It’s a Bluetooth Smart pedal-based system that uses Look Keo pedals with eight strain gauges in each pedal. Transponders plug into spindles on the inside of the crank and zip-tie to the crank arm, similar to the Garmin Vector, the first of this kind (see Vector review in online version at Triathlete.com/powermeters2015), so force is measured directly at the source, the foot/pedal interface. There are two options available: Dual option offers more comprehensive data, and single is less expensive. Claimed accuracy is +/-2 percent.

Best for:
Competitive age-groupers and pros who use a Bluetooth head unit, need highly accurate, on-the-fly data and dual-pedal analysis, and prefer Look Keo pedals. The single option is great for more budget-minded or casual athletes.

The good:
– Easiest to install
– Negligible extra weight (only 200 grams more than standard Keos)
– Dual- or single-pedal power data

The bad:
– No ANT+ limits compatibility
– Precise spindle position tricky to dial, and pedals can loosen unless cranked
– Recalibrations needed regularly

Pair with:
Polar V800—Bluetooth Smart, highly intuitive, great screen, bi-pedal and vector readouts

Ibike Newton 5

$500 with ANT+ speed/cadence sensor, Ibikesports.com

How it works:
The Newton is a lightweight algorithm-based meter, housed in a bike computer that displays power data plus standard ride and GPS data. It calculates power based on wind, hills, acceleration and bike-specific details like aerodynamics and tire resistance.

Best for:
Budget-minded minimalists who don’t need extreme accuracy, especially on the fly, but appreciate one unit that provides power numbers as well as typical computer functions.

The good:
– Compact, light (72 grams), multipurpose
– Works on any road or tri bike

The bad:
– Major fluctuations during ride—claimed accuracy questionable
– Confusing setup and calibrations. Needs regular recalibration. *Editor’s note: New firmware and software have been released to address fluctuation and calibration issues (see online story for test revisions)
– Unit feels a bit flimsy and screen is rudimentary

Pair with: 
N/A. Computer functions are built-in. It is ANT+ compatible with other power meters if desired.

Powercal

$100, ANT+ version ($120, Bluetooth) Powertap.com

How it works:
Developers analyzed tens of thousands of power files to dial a correlation between heart rate and wattage across many conditions and came up with the Powercal, which is the easiest and cheapest option available. Algorithms instantly estimate power based on the rider’s heart rate and send a signal to the device.

Best for:
Casual athletes not obsessed with every statistic, but who want to experiment with power training. Not recommended for riders who rely on on-the-fly numbers to gauge their efforts, as wide variations are typical, especially on short efforts like hills or sprints.

The good:
– Completely portable
– Post-ride data sufficiently accurate and consistent

The bad:
– Wide fluctuations on the fly
– Could easily combine Bluetooth and ANT+ compatibility in one unit

Pair with: 
PowerTap Joule GPS—ANT+, loads of functions, turn-by-turn directions, compact and easy to navigate

Garmin Vector

$1500 ($900 for single), Garmin.com

How it works:
It’s an ANT+ pedal-based system, for road/tri, with strain gauges in the spindles of its Look-compatible pedals. Installation requires a pedal wrench with a torque meter, and you set angles before use. Force is hundreds of times per second, and transmitted through pods that fit over spindles. Since force is measured at the source—the foot/pedal interface—crank flex is not an issue, and readings are leg-specific. Dual (more specific data) and single (less expensive) options, and great transferability to any bike. Claimed accuracy of +/-2%.

Best for:
Competitive age-groupers and pros on a budget, who have multiple bikes and swap them often, and need immediate and accurate on-bike data. Single-pedal option is ideal for even more budget-minded or casual athletes.

The good:
– Consistent and accurate, especially for price
– Easy installation
– Negligible extra weight (50g per pods), no zip ties
– Dual- or single-pedal power data

The bad:
– Requires exact torque on pedal bolt, and angle-set with each install
– Had to recalibrate often
– Pedal had poor connection with cleat