Do You Really Need a Wattmeter?
To figure that out, you should know the answers to the following questions:
What is cycling for you - do you consider it more as a leisure time activity or rather as targeted training and sport?
What are your goals - do you want to participate in competitions and climb the steep ladder to become a professional athlete or just want to ride tours and explore new places just for fun?
How much money do you want to spend on your hobby? Road bike wattmeters and MTB power meters are quite expensive.
What are the advantages of a power meter compared to heart rate measurement or a bike computer? They measure the rider's overall performance, i.e. not just heart rate or speed or average speed, which is often affected by tailwind. In addition, a precise analysis of the performance development often leads to a considerable boost in motivation.
Also, the evaluation of the training in terms of the total training intensity can be determined more precisely. A muscular "burn-out" can be prevented before it is too late.
Find out now how a power meter for bicycles works and what it measures!
How a Bicycle Power Meter Works
During cycling, a very exact measurement of the directly physical total power in Watt is possible. Bicycle power measurement will be performed by sensors called strain gauges, which record the mechanical twisting (torque) or the force exerted.
Internal microelectronics, protected according to industry standards, which can even take weather conditions into account, calculates the values using a formula. This formula is as simple as it is ingenious.
Power = mechanical torque x cadence
Afterwards, the internal electronics transmit the data wirelessly via ANT+ or Bluetooth to your handlebar display, your bike computer, your navigation device or simply to your smartphone. These devices, which are separately available at BIKE24, clearly display your performance and analyzed data.
Which Values and Data Does a MTB or Road Bike Wattmeter Provides?
Among the basic functions of bike meters are the calculation of total power in watts - minimum / maximum and average. And of course it also determines cadence and speed.
Rather high quality systems also offer separate power measurement of the left and right leg.
Also widely common is the calculation of the vertical gain, the metabolic rate and the display of the current altitude and temperature. It is furthermore possible to perform performance tests for your FTP (functional performance threshold), VO2max and lactate threshold.
Finally the best feature: With the help of a cycle power meter road cyclists, mountain bikers and triathletes can ride specific intervals. One of the most important methods to effectively increase power endurance.
The strain gauges required for measurement can be integrated in various bicycle components.
The Different Road Bike / MTB Powermeters
Crank Based Systems
The determination of the power via a crank is probably the most frequently used method. Power meter cranks are considered very accurate with a deviation of +/- 1.5%.
The strain gauges for measuring the torque can be located in or on the crank arms, in the crank spindle or in the spider (installation location of the chainrings). Via the crank arms and the shaft a separate power measurement for the left and right leg is possible. More affordable crank spindles and spider systems usually measure only one side and the displayed values are calculated, which can lead to inaccuracies.
The crucial advantage of the corresponding MTB power meters and road bike wattmeters is the separate upgradeability of crankspiders and crank spindles when using modular cranks.
However, assembly can be tricky, and should only be carried out by technical experienced riders or bicycle mechanics with the appropriate tools. Otherwise it can happen that the bicycle power meter is not calibrated correctly and incorrect measured values are displayed.
Pedal Based Systems
Pedal-based wattmeters are also very popular on road bikes. They can achieve an even greater accuracy with deviations of only +/- 1%. The strain gauges are placed inexpensively on one side or on the left and right pedal axle. A further argument for separate measurement is the possibility to detect muscular imbalances early and to counteract them. The biggest advantage of these cycle power meters is the extremely easy installation. Due to their design, pedals with integrated power measurement are slightly more vulnerable to environmental influences and more susceptible to weight overload.
Hubs for Bike power Measurement
Rather rarely are hubs or wheels the basis for a wattmeter, because knowledge of wheel building is necessary. With regard to accuracy (+/- 1.5% deviation), however, they do not have to hide behind their competitors. The strain gauges are located in the rear wheel hub, on the non-drive side directly on the axle, which is why only the measurement of the total power is possible. This optically most inconspicuous solution for bike power measurement can be used without tools on different bicycles of the same type without any problems.
Buy Products for Bike Power Measurement at BIKE24
A road bike and MTB power meter is a major investment, but it will pay off if it is adapted to your individual requirements. In addition to bicycle wattmeters, you will also find suitable accessories and spare parts in this category.