THE BEGINNER’S GUIDE TO POWER METERS
You have been cycling for a while, and you just heard of power meter cycling. You heard it’s awesome, but have not made up your mind. Should you buy one? What are the types? How much do they cost?
What is a Power Meter?
Put simply, it’s a device that measures the power output of a bike. Technically, they are able to do this because they have strain gauges that deflect when force is applied to them. They combine the torque with angular velocity to determine the measure of watts used.
The Different Types of Power Meters
Presently, riders can place them in five key areas of a bike. Determining the best cycling power meter for you depends on the advantage and disadvantage of each. The key areas are:
- Rear wheel hub
- The Bottom bracket
- Crank arms
Rear Wheel Hub: This type of setup is the simplest form. Since there are fewer external forces acting on the strain gauges, a lot of engineers think the hub is the best place to accurately measure output.
However, the measurement here would be lesser than what you would get on a pedal or crank power meter. This is because you are measuring what is left post drivetrain loss. The output can also be lower if the drive chain is quite dirty.
Bottom Bracket Systems: This type is quite accurate and requires little maintenance. However, it can be quite difficult to install. This is made more complicated by the different bottom bracket standards. This makes it harder to swap them between different bikes.
Chainring System: These types can be quite accurate. But you should note that they don’t measure the left/right leg output. However, they can give reliable estimates. Just like bottom bracket, they are not easy to swap between bikes.
Crank Power Meter: Unlike the last two, you can easily swap this one between bikes. They can also be single or double sided. If you want to get one, you can check out Stages power meters for sale.
Pedal Systems: These kinds are easy to swap between bikes. However, they are not quite accurate because of the complex force measurements. They also face a lot of exposure and can easily get damaged.
Power Meter Placement
This categorisation differentiates devices by the side of the bike they are placed on. They can be placed on the left side, right side, or on both side. Placing them on a particular side of the bike measures the output produced by the leg in that position.
These types are located on one side of the bike, usually the left side of the bike. They measure the output from one leg, and double it to give an estimate. They might not be fully accurate, but are quite affordable.
Before you get a single sided meter, check if you have significant imbalances. The common left/right balance is 48/52 pct.
This type measures the output produced by both sides of the leg. They are more accurate than the single sided devices. However, they cannot give you a measurement of the output produced by a single leg.
Side Independent Meters
These types are more expensive and sophisticate. They are also placed in multiple places like the crank and the pedal. They measure the unit each individual leg produces. With this, you would be able to establish which leg is producing more.
They would also be especially useful if you are recovering from a leg injury. With them, you can measure the improvement in the output your injured leg produces.
How much Do They Cost?
The type of meter you use depends on your budget. So, it would be best if you know what you are likely to get with the present sum in your pocket.
Entry Level ($400 to $700)
With a budget in this range, what you would get are road bike power meters that measure the output from a single leg and estimate them for both legs.
Mid-Level ($700 to $1100)
At this range, you are going to come across pedal, crank, and chain ring systems. They would also be dual sided. This is the range for professional athletes.
Top End ($1200+)
With this budget, you are going to get combined and dual sided systems. You are also going to encounter crank and spindle systems.
How are Power Meters Useful?
If you are interested in determining how hard you are actually working, then you need to calculate your output. Calculating your speed tells you a little about the ride, while your heart rate tells you a bit more. On the other hand, power outputs give you a quantitative and objective means of calculating your input.
For example, you might have a slower speed during a route, or your heart rate is slower. But if your output data is up, it shows that you are really putting in some work.
They also give you pointers when that it’s time to rest. If your heart rate is above a certain rate at a predetermined level, that is a signal that you need to head home.
Another advantage of measuring your output is that it helps to define your weakness. If you notice a reduction in output on a consistent basis, then you need to put in more work.
You also get to train for the specific demands of an event. Some events specify the kinds of outputs that would be required before you participate. When you have trained consistently with a meter, you would be well prepared for whatever the organisers throw at you.
One last thing to keep in mind before you buy one: Make sure you take a fitness test. With this, you can determine what your starting point should be. You also get to be able to set the right goals for your training exercises. You should also have a clear idea of how you plan on using it.