What’s the benefit of a bike speed sensor
Quite simply a speed sensor will give more accurate readings of not only your speed but also your distance. If you already have a Garmin Edge device, or similar bike computer, then you’ll likely be aware that this already offers a speed metric. A GPS cycling computer uses the GPS data it takes in to calculate your speed. Since it’s reliant on the GPS signal, while typically accurate, it’s vulnerable to fluctuations depending on the strength of the GPS signal available. For long road rides in open areas this isn’t likely to be a significant issue. However, if you primarily ride off road, in locations with dense tree cover or buildings, or regularly tackle steep inclines then a speed sensor can give you more confidence in the readings.
How does a speed sensor work?
A speed sensor is a small electronic device that you strap to the outside of the hub of your rear wheel. A Garmin speed sensor contains magnetometers that measure the three-dimensional components of the ambient magnetic field. As your wheel rotates, the meter measures its own rotation within the surrounding earth’s magnetic field. You might think that, since it’s using magnets, it’ll be vulnerable to interference from metallic or magnetic objects on the road. But fear not, these devices are designed to take account of potential causes of interference.
Cadence Sensor
A cadence sensor has a similar look and feel to a speed sensor, except that it attaches to the left crankarm of your bike. Fairly obviously, a cadence sensor will calculate your cadence — which is the number of pedal strokes you take per minute or “revolutions per minutes” — and then display this to your cycling computer.
A cadence sensor can offer useful data and act as a training tool. If you’ve wondered if you’re a “grinder”, a “spinner”, or something in between then hook up a cadence sensor and find out. If you want up your cadence to the washing-machine-like frequency of Chris Froome, then a cadence sensor is way to go. You’ll be able to see what you’re currently doing and train to increase it.
Indoor Cycling
If you’re looking to enter the world of indoor training, without having to spend hundreds of pounds on a smart trainer, then a speed and cadence sensor represent a more budget version to start training indoors. With these sensors on your bike, you’ll be able to get ‘virtual’ power on most platforms, which is essentially an estimate of your power. That means, you’ll be train and ride to power on training platforms like Zwift and TrainerRoad.
