On this page, I explain how I test and score power meters so you get a better idea of the details. Each category’s results contribute to my overall verdict on the power meter’s quality.
I evaluate them on a scale of 1-5, where 1 is the worst and 5 is the best. It looks as follows:
Accuracy 4/5 | Reliability 4/5 | Ease of Installation 3/5 | Battery Life 5/5 | Price 2/5 | WEIGHTED OVERALL SCORE 3.8/5
Scores 1–2.5 are RED, 2.6–3.9 are ORANGE, and 4–5 are GREEN.
I score the following criteria on a scale mainly based on in-depth market research, which includes evaluating my and other owners’ experiences and comparing the power meter features with competing alternatives. The scores are weighted, meaning each feature has a different importance. For example, the accuracy is more important than the battery life.
I approach each power meter as objectively as possible. However, like everyone, I am subject to biases and expectations.
Scoring Criteria for Power Meter Features
Below is the list of the features of power meters with an explanation of the scoring.
Accuracy
I distinguish between claimed and measured accuracy. The claimed accuracy is that of the manufacturer. The measured accuracy is what I get from a series of tests and comparisons with other power sources.
The test series includes 3 basic tests:
- ERG mode
- Freeride
- Race
I convert the measured accuracy to positive numbers and average them. I do the conversion to find the average deviation from the base. If I averaged the values of, e.g., 1% and –1%, the deviation would be 0%, which is mathematically true, but realistically it gives a false idea about the power meter’s accuracy. After the conversion, the accuracy is ±1%.
I also analyze the data from the on-bike power meters. The main data source I use is Favero Assioma DUO power meters. They have a claimed accuracy of ±1% and are among the most reliable pedal power meters. I use them as a base. The second power meter is usually a spider power meter like the Magene P505. When comparing pedal power meters, I use Wahoo KICKR v5.
Before testing, I always update the power meter to the latest firmware and perform the zero offset. I don’t do manual zero offset before each ride if the power meter has auto-zero.
Here are the points and the accuracy intervals. For power meters that I have not tested yet, I base it on claimed accuracy.
- 1 – The measured accuracy is worse than ±4%.
- 2 – The measured accuracy is (±3-4%].
- 3 – The measured accuracy is (±2-3%].
- 4 – The measured accuracy is (±1-2%].
- 5 – The measured accuracy is better than ±1%.
For an illustration, here are the claimed accuracy rates of the best power meters:
Reliability
Accuracy is one thing, but reliability is another important feature because if the power meter shifts the baseline over time, you can’t rely on it. Due to the limited amount of data that I am able to obtain as an individual, I study the experiences of other users who discuss on forums such as TrainerRoad or Reddit. Regarding reliability, I look at how customer support responds to problems and how the brand looks after its reputation.
- 1 – E.g., an unreliable power meter that doesn’t provide consistent data (Shimano power meters).
- 2
- 3
- 4
- 5 – E.g., a reliable power meter that provides consistent data (Favero Assioma).
Ease of Installation
The ease of the installation involves mainly installing the power meter on the bike. Pedal power meters are the easiest to set up, followed by crank arm power meters. Crankset or spider power meters require more time for installation.
I have the following scoring:
- 1 – BB power meters.
- 2 – Spider power meters.
- 3 – Crankset power meters.
- 4 – Crank arm power meters.
- 5 – Pedal power meters.
Battery Life
I don’t currently have a standardized test available, and given the 200+ hour battery life of some power meters, it would be impractical to test it. So, I use the claimed battery life for scoring. Whether the battery is rechargeable is not factored into the rating, but it is good to keep this shortcoming in mind.
The scoring is as follows:
- 1 – Below 50 hours.
- 2 – [50–100) hours.
- 3 – [100–150) hours.
- 4 – [150–200) hours.
- 5 – Above 200 hours.
Below are some of the selected power meters and their claimed battery life.
Price
I also included the recommended retail price (RRP) in the evaluation, although its perception is highly subjective. That’s why it has a relatively small weight in the overall rating. With crank arm power meters, I count with mid-range groupset ‘ride ready’ option, for example, 4iiii Precision 3 for Ultegra groupset.
The evaluation is as follows:
- 1 – Above $1000.
- 2 – Between $800 and $999.
- 3 – Between $600 and $799.
- 4 – Between $400 and $599.
- 5 – Below $400.
Conclusion
I try to be as objective as possible when testing power meters (and all other products). I aim to communicate my experience to potential buyers and help you make educated buying decisions.
Please remember that I am still tweaking and improving this procedure to provide you with the most valuable information possible.
I am open to suggestions on how to improve. Feel free to contact me. Here is the list of all the power meters I reviewed:
Recent Updates
- Feb 8, 2024: V1.0 testing procedure introduced.