Power meter for road bikes: Pedals or cranks - which is better?

Road bike powermeter: Pedal or crank?

If you want to measure your performance with several bikes, there's no getting round pedal power meters. In the test, the Favero pedal proved to be variable and accurate. We generally consider the crank power meters with measurement in the crank spider to be more robust - the measurement technology is better protected and not quite as miniaturised.

>> Power measurement on a road bike: 9 power meters tested

Single or double-sided power meters: which is better?

Measurement on both sides is clearly preferable. As the legs are rarely equally strong, accuracy suffers if the power of one leg is simply multiplied by two - which is exactly what one-sided measuring systems do. We think so: If you are going to measure, do it as precisely as possible. If, for example, 48 per cent of the pedalling force is distributed to the left leg and 52 per cent to the right, the +/-2 per cent measurement tolerance becomes a range of -2 to +6 per cent.

Real measurement on both sides?

Only dual crank or pedal power meters provide an accurate resolution for left and right legs. With the classic measurement in the crank star, the total is recorded correctly, but the left-right display is inaccurate, as it is unclear what contribution the legs make in the pulling phase.

Built-in rechargeable battery or replaceable battery?

Nothing works without electricity. Either an internal rechargeable battery or replaceable batteries power the power metres. The advantage of the permanently installed battery: greater reliability and better water resistance. Battery contacts are often a source of faults, the covers and screw connections are mechanical sources of faults. However, if the battery is defective, the device must be sent in.

Compatibility with your own racing bike

Only power meter pedals are fully compatible with all bikes. You may need to fit washers if the cranks require them or if the axle is too close to the frame. For crank power meters, you need to check the bottom bracket type and also whether there is enough clearance between the chainstay and the sensor housing. This applies in particular to the Stages design with a small box on the back of the crank - most, but not all frames are compatible here.