Optimizing for terrain: 4iiii adds firmware update to PRECISION 3 Powermeter
The latest firmware update for 4iiii Innovations’ 3rd generation power meter has just been unveiled. The upgrade, which 4iiii markets as a game-changer for cyclists, dynamically switches between a gyroscope and accelerometer as the main source for cadence depending on the surface smoothness and cadence.
Q: Why Does This Matter
Pedal/Crank-based Power Meters need to know your cadence to determine power. If, for whatever reason, revolutions are missed then your power accuracy will fall.
Super-high cadence rates and non-smooth surfaces can give missed revolutions when accelerometers are the source of cadence
Q: What’s the alternative?
Other companies, like Stages Cycling and now 4iiii, incorporate a gyroscope within the power meter. This increases certainty but also increases battery consumption.
Thus, unlike Stages, 4iiii dynamically switches to the gyroscope only when needed, theoretically getting the best cadence on all surfaces for the lowest battery consumption.
Q: Anything Else?
Yes, 4iiii claim both an instant start-up response and the ability to handle up to 220rpm (not tested 😉 )
Plus you can get a sneaky discount as shown below
Buy one and get a 3-Year Warranty
4iiii offers a generous 3-year warranty.
Ride-ready cranks start at $/£/Eu324.99 with the Shimano 105 R7000 and increase 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)
Last Updated on 26 January 2026 by the5krunner
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tfk is the founder and author of the5krunner, an independent endurance sports technology publication. With 20 years of hands-on testing of GPS watches and wearables, and competing in triathlons at an international age-group level, tfk provides in-depth expert analysis of fitness technology for serious athletes and endurance sport competitors. See the gear tfk uses. ID
