Understanding Wattbike Calibration AccuracyUpdated 2 days ago

Understanding Calibration Accuracy

Calibration is fundamental to ensuring your Wattbike delivers accurate, repeatable power data. Every Wattbike is precisely calibrated during manufacture to establish a known baseline. However, like all precision mechanical systems, calibration accuracy is not fixed for the entire lifetime of the bike.

This article explains why calibration can change over time, what affects it, and why specialist recalibration at Wattbike HQ may occasionally be required.

What Is Calibration?

Calibration is the process of aligning the Wattbike’s internal measurement system with known, traceable reference values. This ensures that the power you see on screen accurately reflects the power being produced at the pedals.

Factory calibration sets this reference point under controlled conditions using specialist equipment.

Why Calibration Changes Over Time

Although the initial calibration is extremely accurate - to a tolerance of +/- 1% across the entire power range, a Wattbike is a mechanical system that experiences ongoing physical use. Over time, several factors can subtly affect calibration accuracy:

• Component wear
  Bearings, chains, resistance components, and other moving parts naturally wear with use. Even very small changes can alter how forces are transmitted through the system.
• Mechanical settling and movement
  Repeated loading, high power outputs, and long-term use can cause microscopic shifts in the relative position of components involved in power measurement.
• Environmental and usage factors
  Heavy commercial use, high training loads, transportation, or repeated assembly and disassembly can all contribute to gradual changes in mechanical alignment.

Individually these changes are small, but collectively they can influence calibration accuracy over time. Our servicing teams are trained in understanding the sensitivity of our power measurement systems and will take this in to account during a service.

Setting 'Zero State' vs. Full Calibration

It’s important to distinguish between setting the zero state and full calibration:

• Set Zero State - performed by the user - ensures the system starts each session from a known unloaded state and helps maintain day‑to‑day consistency.
• Full calibration realigns the Wattbike against certified reference equipment and accounts for accumulated mechanical changes that zeroing alone cannot correct.

Set Zero State is strongly recommended for regular/intense users - but it cannot compensate for long‑term mechanical wear. All Wattbikes have a function built in for the bike to perform a 'set zero state' automatically. The bike will detect periods of inactivity and evaluate readings from the strain gauge to set the zero state value correctly.

Why HQ Calibration Is Sometimes Required

To restore and guarantee calibration accuracy, the Wattbike must occasionally be recalibrated using specialist calibration machines that are only available at Wattbike HQ.

These machines:

• Apply known, traceable loads
• Measure system response across the full power range
• Allow precise mechanical and electronic adjustment

This process ensures the bike will continue to meet Wattbike’s calibration accuracy standards. 

When Should Recalibration Be Considered?

Recalibration may be recommended if:

• The bike has seen high usage (especially in commercial or performance environments) and is required for critical performance testing
• There are persistent discrepancies compared to other trusted power measurement devices*
• The bike has undergone major servicing or electronic component replacement (this will generally only be required for services completed at Wattbike HQ)
• Maximum measurement accuracy is required for testing, research, or elite performance use
• You are about to undertake a critical block of training or intend to compete in an e‑racing or virtual league where power data is subject to validation or scrutiny, recalibration may be advisable to ensure confidence in reported power values.

*Differences observed when comparing to other power measurement devices may reflect variations in measurement location, system losses, and calibration methodology rather than true inaccuracies, as cross‑device comparisons are inherently limited outside of controlled reference testing.

Calibration, Age, and Service History

Calibration accuracy is closely linked to both the age of the bike and its service history. While Wattbikes are designed for long‑term durability, mechanical systems benefit from periodic inspection, adjustment, and servicing to maintain optimal performance.

Recalibration may be required in the following age and service related scenarios:

• Bikes over 5 years old that have never received a full service
  Over extended periods without servicing; cumulative component wear and mechanical settling may exceed the corrective scope of zero‑state adjustments alone.

• Bikes over 7 years old with two or fewer recorded services
  Even with moderate use; long service intervals can allow gradual mechanical changes to accumulate, potentially affecting long‑term measurement accuracy.

Wherever possible, calibration should be carried out in conjunction with a full service. Servicing allows worn or fatigued components to be identified and corrected before calibration is applied. Performing calibration independently of a service may not restore accuracy as effectively and, in some cases, can lead to further adjustment being required sooner than expected.

Aligning calibration with servicing ensures the Wattbike is mechanically optimised before reference alignment, delivering the most stable and reliable accuracy over time.

Calibration and servicing costs are outlined here. 

Our Commitment to Accuracy

Wattbike designs its products to be robust, reliable, and highly accurate. However, accuracy is not a static condition - it is something that must be maintained over the working life of the bike.

Occasional specialist recalibration is not a fault; it is part of responsible ownership of a precision performance instrument.

If you believe your Wattbike may require recalibration, our support team can advise on inspection and servicing options.