4iiii Precision 3 Power Meter – Slimmer and slightly more accurate…sometimes

4iiii precision 3 review specifications
Dual-sided version shown

4iiii Precision 3 Power Meter

4iiii’s latest crank-based power meter claims market-leading +/- 1% accuracy, wider frame compatibility and a battery that will last for a very long time.

Right now, only the single-sided version is available. That’s OK though, as its sensible price makes it a very attractive entry-level option for newbie power riders.

There are a few interesting things to talk about here ranging from LEDs to a novel way of potentially measuring accuracy in an ever-so-slightly better way.

It will almost certainly work with any training platform you use like Zwift and any power-compatible bike computer (Garmin, Wahoo, Hammerhead) or sports watch (Garmin, Polar, Suunto, Apple Watch w/iSmoothRun).


4iiii Precision 3 – What do I need to know?

Let’s quickly cover all the talking points


The battery is not rechargeable but the CR2032 ‘coin cell’ battery is replaceable and should give you up to 800 hours of ride time. That’s at least 4x that of the comparable Stages Gen 3 Power Meter (150-200 hours). and realistically that’s around 10x longer than you get from even the best power meter pedals.


At 9g (left)  it’s the lightest power meter on the market, and that’s about half of the Stages Gen 3. However, I don’t think these levels of weight saving are important for 99% of us.

Accuracy in 3D

The accuracy is stated as +/- 1% and is verified by the University of Boulder, Colorado. Again, this is supposedly slightly better than the Stages Gen 3 at +/- 1.5% but I just don’t think that difference matters, especially with a single-sided power meter. You can scale the power up or down to take into account any imbalance you might have.

Temperature variations can affect power measurement and 4iiii claims that their active temperature compensation is up to that job. Most of us needn’t worry too much about that but for long rides or high elevation gain rides this could become an issue if it’s not as good as claimed (same with other manufacturers)

Interestingly, accuracy is probably further improved as 4iiii has a novel 3D strain gauge. As you tire throughout your ride there will be twisting movements and lateral movements that are different from when you are fresh. AFAIK 4iiii is the only company claiming to take these into account at anywhere near this price point.

Single-Sided or Dual-Sided? – Your Crankset? or buy the whole thing?

You can have these installed onto your existing cranks at your local service centre or you can buy new cranks directly from 4iiii where their power meter comes preinstalled. Currently, the pre-installed option is available on a wide range of Shimano cranks (see image to right, March 2022).

The dual-sided version will come later in the year and you can upgrade to it. Similarly, the new, single-sided Gen 3 crank is backwardly compatible with the Gen 2 right-side cranks. Though why you’d do that, I don’t know.


At a mere 5.5mm, 4iiii’s new power meter is VERY thin. This is only relevant if you have certain kinds of frames where there is minimal clearance between the crank and frame.


The LEDs on a power meter can make the difference between ambivalence and knowing if your bike really is ready to go.

If it’s green you’re on and ready to go, blue means calibrated and red means low battery.


4iiii Precision 3 Specifications

Key 4iiii Precision 3 Specifications1
Accuracy+/- 1%
Battery TypeCR2032 Coin Cell
Battery Life<800 hours
Cycling DynamicsYes, cadence, Torque Effectiveness and Pedal Smoothness
Cadence Range30 – 170 rpm
Power Range0 – 4,000w
Environmental0 to 50 °C temperature and waterproof to IPx7
Communication ProtocolsANT+, Bluetooth

4iiii precision 3 review specifications

Buy one and get a 3-Year Warranty

4iiii offer a generous 3-year warranty.

Ride-ready cranks start at $/£/Eu324.99 with the Shimano 105 R7000 and increasing upwards depending on the value of the crank you buy.

It costs $/£/Eu299 to install on your existing cranks regardless of the model (or currency!) and this typically saves you about 30%.

Get yours here from Wiggle or use the code the5krunner10 for a 10% discount at PowerMeterCity (USA)


buy 4iiii precision gen 3 discount


Verdict: Accurate, long-lasting and a cost-effective choice for beginners or riders of any ability
  • Price - 90%
  • Apparent Accuracy - 99%
  • Build Quality & Design - 90%
  • Features, Including App - 90%
  • Openness & Compatability - 90%

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