Beginner’s Guide to Power Meters
New to power meters? You came to the right place! We wrote this Beginner’s Guide to Power Meters just for you. This guide is specifically designed for those new to power who want to get up to speed fast. What a power meter is, how they work, the different types, etc. Oh, and how you’ll benefit from using one! After reading this guide, you’ll know all the basics and will be well on your way to getting powered up!
Please note that since this guide is geared towards cyclists that are new to power, our goal is to hit all the important points, without going too deep into the weeds. After reading this guide, if you want to take your knowledge to the next level, great. Check out our Power Central where we have loads of power meter related content and resources. Ok, let’s get started!
You can click on any topic above to jump straight there.
1. What is a Power Meter?
A power meter is an electronic device that measures the power, or torque, the rider generates when they turn the pedals. Hence the term ‘power meter’ – it is literally metering, or measuring your power. There are several different types of power meters, depending where on the bike the power meter is located. For example, you can buy a crank-based power meter, where the power sensors and electronics are built into the crank, or a pedal-based power meter where the sensors and electronics are located in the pedals. You can put a power meter on virtually any bike – road, mountain, track, cyclocross, BMX, etc.
Power is a measurement of the work you do on the bike and is the most accurate way to measure your effort. Power meters measure power in watts.
As an example, here are two popular power meters:
Favero Assioma DUO
2. How Do Power Meters Work?
Most power meters measure torque using what is called a strain gauge. A strain gauge is a tiny electronic device whose electrical resistance varies depending on how much resistance (strain) is put on them. In the case of a crank arm-based power meter for example, the strain gauge measures how much your crank arm is flexing when you push down on the pedals.
Graphical depiction of a strain gauge. Provided by Quarq
Using electronics located within the power meter, the strain gauge converts this flex into an electrical resistance. Based on the amount of electrical resistance, the power meter can calculate how much torque the rider is generating.
The number of strain gauges, their alignment and the materials used all determine how accurate a power meter is. The precise measurement of torque is the biggest challenge power meter manufacturers face. The microscopic bending that the strain gauges must precisely measure is the key to accurate results. It requires an extremely high level of engineering and precision to fit the strain gauges within a power meter.
Data from the power meter is transmitted in real-time to a handlebar mounted computer or sport watch (‘head unit’) via a wireless protocol such as ANT+ or Bluetooth SMART. The head unit displays power data such as current, maximum and average power, as well as serves as an all-around cycling computer, displaying things like heart rate, speed, distance time and much more. Note that Bluetooth SMART also allows power meters to interact with smartphones and tablets.
As an example, here are two popular head units:
SRM PC8 PowerControl
Garmin Edge 520
3. Benefits of Training with Power
With cycling, many things affect how fast you go. Winds, gradients, weight, road surface and more all determine your speed, so it’s very difficult to gauge precisely how hard you’re working. With a power meter, you can directly measure your work rate and fitness. It takes the guesswork out of riding and allows you to quantify your efforts. Power meters provide an objective measurement of real output. This affords the rider numerous advantages.
Power meters have become essential tools for cyclists of all levels, their coaches as well as sports scientists – who use power meters as a fundamental way to measure and improve cycling performance. Power meters can unlock more endurance and speed than any other training tool.
Here are just a few of the ways you can use a power meter to improve your performance:
1. Eliminates Guesswork
Perhaps the biggest advantage to a power meter is that it removes the guesswork that goes into training and racing. With a power meter, you can quantify exactly how hard you are working (as your effort is directly measured in watts). Many people use a heart rate monitor in their training. However, heart rate monitors only tell you how hard the effort is to your body – they don’t tell you the actual amount of work you are performing. Watts are a much more accurate way to measure your effort.
2. Allows for Structured Training
When you just start out, you can improve your performance by following the ‘just ride lots’ technique. But soon, you will start to see your improvement slow. A structured training program where you focus on different intensities at varying durations is the ticket to continued improvements in power and performance.
3. Can Track Fitness More Accurately
Power meters provide highly accurate details about how your fitness is changing throughout the season. You can closely track your average power numbers at given distances, your maximum power numbers, your functional threshold power and more. Using software like TrainingPeaks and their Performance Management Chart for example, you can track of variety of important metrics. The information gained from this type of software and analysis is invaluable.
4. Race Pacing
We all know that in most long, steady-state races such as a triathlons and time trials, your best strategy is to pace yourself. You don’t want to start too hard and end up limping to the finish, nor do you want to start too easy and finish with gas left in the tank. Well a power meter allows you to pace yourself almost perfectly. Once an athlete’s optimal power has been determined with a power meter, they can gauge exactly how hard to push during a race.
With a power meter, there’s no lying. You get immediate, accurate performance assessment. This can serve as a great motivational tool. There is nothing more satisfying then ending an interval or a ride and seeing an increase in your average or maximum power numbers. A power meter can really help you hit that 100% effort target and can serve as a great training tool because of this alone.
6. Communication with Your Coach
If you have a coach or are thinking about getting one, a power meter greatly improves the value that they can provide. A power meter will provide a wealth of data for your coach. In addition to power, things like speed and cadence are also informative. With this data, the coach can create a plan that is tailored to your needs and by continuing to view data from your rides, they can closely monitor your performance and make adjustments where necessary.
4. Types of Power Meters?
Power meters have been around for quite some time, however in just the last few years, the power meter market has blown wide open. In addition to better power meters, we are seeing new manufacturers enter the market with more types of power meters than what previously existed.
The “type” of power meter refers to where on the bike the power meter measures power. For example, some power meters are built into your crank and measure force at the crank spider – whereas other power meters are built into the pedals. Currently, there are 7 locations on the bike to measure power.
1. Crank (Spider)
3. Crank arm
4. OFPM (Handlebars)
5. Bottom bracket
1. Crank (Spider)
Crank-based power meters are located on the cranks of the bike and measure torque using a strain gauge positioned inside the crank spider. These units require specific cranks or cranksets, but can be interchanged between bikes, depending on compatibility. Crank-based power meters are some of the most common power meters and are the most heavily adopted system by professional athletes.
Pedal-based systems incorporate strain gauges inside the pedal itself. Favero, PowerTap and Garmin all make pedal-based power meters. Pedal-based systems are perhaps the most popular power meter. They are easy to install, simple to use and are compatible with almost any bike. These power meters all come with a proprietary, Look Keo style cleat that must be used with the power meter. Note that the Favero and Garmin pedals can also be used with a Look Keo original cleat.
Favero Assioma DUO
PowerTap P1 Pedal
Garmin Vector 3
3. Crank Arm
A crank arm-based power meter measures the forces in the crank arm. However, there are different variants of crank arm-based power meters. The Verve InfoCrank is a complete crankset (crank arms, spider and chainrings) and has a power sensor on both the left and right crank arm. The WATTEAM POWERBEAT also locates a power sensor on both crank arms, however it is a user installed unit and there is no need to purchase new crank arms, spider or chainrings. Since both of these power meters have a power sensor on both crank arms, they can measure power from both legs independently. Data from both power sensors is combined to give you total power.
Companies such as 4iiii, Stages Cycling and Pioneer sell a left side only power-equipped crank arm. The left side crank arm doubles your left leg power in order to get a total power figure. This method of calculation assumes that both legs produce the same force. While not able to measure both legs specifically, left only crank arms can be more affordable and are simpler to install. Note that while 4iiii, Stages Cycling and Pioneer are known for their left side power meters, they also produce complete cranksets capable of measuring dual-sided power.
4. OFPM (Handlebars)
Velocomp produces a handlebar mounted power meter called the PowerPod. Unlike direct force power meters (which are all the other types of power meters discussed in this article) that measure your power using strain gauges, the PowerPod attaches to your handlebars. It measures your power through wind measurement – the forces that oppose the rider. This is called opposing force technology. The PowerPod uses an accelerometer, a wind pressure sensor, an elevation sensor and a speed sensor – all to measure power. There are some advantages and considerations to this type of power meter. If you’re interested in learning more, have a look at our Direct vs. Opposing Force Power Meters article where we discuss this in detail.
5. Bottom Bracket
Bottom bracket power meters are similar to crank-based power meters in that your current crankset is often replaced for a new, power-equipped one (but not always, as the CINCH allows you to just purchase the spindle). However the location of power measurement differs. Bottom bracket-based power meters measure torque in the axle. ROTOR manufactures its INpower and 2INpower power meters. Likewise, Easton and Race Face offer their CINCH power meter.
Easton & Race Face CINCH
With a hub-based power meter, the strain gauges are located in the rear hub and measure power through the drive chain. PowerTap remains the only manufacturer of a hub-based power meter. You can purchase a stand-alone G3 hub for as little as $399 or buy a complete wheel where the hub is already laced into a new wheelset (this option is of course a bit more expensive). PowerTap’s G3 hub has been a go-to power meter for years and remains a very popular option among cyclists of all levels.
PowerTap G3 Hub
PowerTap G3 Rear Disc Hub
PowerTap also manufactures the C1 Chainring. Similar to the crank-based cycling power meters discussed above, the C1 measures power at the crank. However the exact location of power measurement is different. SRM for example, measures power at the crank spider. PowerTap measures power on the chainring by locating a sensor on the outside of the small ring. The PowerTap C1 Chainring is the only chainring-based power meter.
PowerTap C1 Chainrings
5. Our Most Popular Power Meters
We thought it would be helpful if we listed our most popular power meters. This is like a cheat sheet of some of best power meters and values you can find. This isn’t to say all of these power meters are perfect for you…but if you’re new to power, this is a good place to start.
Cost: $399 (dual-sided). $259 (single-sided)
- Most affordable direct force power meter
- Independent left/right power
- Very light (less than 20 grams per side)
The WATTEAM POWERBEAT is the first user-installed power meter with features, functionality and accuracy once found only in factory installed units. At $399 (dual-sided), it is the most affordable, direct force power meter capable of measuring total power (power from both legs), plus independent left/right power as well. It is extremely lightweight and features ANT+ as well as Bluetooth SMART.
- The most affordable power meter pedals
- Simple to install
- Independent left/right power (DUO)
The Assioma DUO offers all of the benefits of a power meter pedal (dual-sided power, easy to use, compatible with all bikes, etc.), but at a lower price point than other pedals – making it one of our best-selling power meters. It also has a fantastic track record of reliability and dependability.
Favero Assioma DUO
Bike: Road and MTB
- The most affordable crank-based power meter (Road Alloy)
- Uses Power2Max’s proven spider design (accurate and reliable)
- Full of features (Auto Zero, user friendly battery, L/R power, BLE, etc.)
The FSA PowerBox is a crank-based power meter, measuring power at the spider. It uses Power2Max’s proven spider design and comes with FSA chainrings and crank arms. The result is an accurate, extremely versatile power meter that comes with top-notch FSA components. Best yet, it is the most affordable crankset-based power meter on the market.
Bike: Road and MTB
- One of the most affordable direct force power meters
- Lightest power meter (added weight)
- Easy to install
The 4iiii PRECISION and Podium is the lightest and one of the most affordable direct force power meters (only the PowerBeat Single is cheaper). It’s accurate, super reliable and simple to install. There are versions for Shimano road and MTB cranksets.
4iiii PRECISION | Podium
Bike: Road and MTB
- Compatible across a wide range of cranksets
- Easy to install
- Offer both single and dual-sided power measurement
Stages power meters have been very popular for a number of years now. Being a single-sided crank arm, it is easy to install and use. It features 200 hours of battery life, is extremely lightweight – adding only 20 grams to the weight of the crank arm and is compatible with both ANT+ and Bluetooth SMART devices. In addition, Stages makes a power meter for almost any crankset.
- Affordable with models starting at $299
- Compatible with any bike
- Light weight
- Easy to move between bikes
Unlike other power meters on our list which measure torque with strain gauges (direct force power meter), the PowerPod attaches to your handlebars and measures your power through wind measurement (opposing force power meter). While this type of power meter isn’t for everyone, it does offer some nice advantages over a more traditional power meter. Note the base PowerPod is $299. As you add options and features (PowerStroke, Bluetooth, etc.), the price increases.
Garmin Vector 3
- Easy installation allows the Vector 3 to be installed just like a normal pedal
- Slim pedal design resembles a traditional pedal in look, size and shape
- Independent left/right power
The Garmin Vector 3 features left/right power, Bluetooth SMART as well as Garmin’s Cycling Dynamics when used with a Garmin head unit. While the previous version of the Vector was met with mixed reviews, the Vector 3 has received high marks for its easy to use design and slim form.
So you’re convinced that a power meter is the single most effective training tool a cyclist can use for improving performance, but you think they are too expensive? We would argue differently. Cyclists often spend hundreds and sometimes thousands of dollars upgrading the components on their bike…and we can’t think of a single upgrade that can offer the potential gains that a power meter can. Power meters are simply an invaluable piece of technology when it comes to cycling performance.
In addition, due to the rise in popularity and the increased use of power meters across all cycling disciplines, more manufacturers have entered the market. More power meters results in a more competitive environment, which means lower prices. With prices now starting at $259, there is no reason not to be riding with power!
7. How to Choose a Power Meter
At this point, you are well versed on power meters. All that is left is to find the one that is right for you. This means deciding on which power meter type you want, determining the ones that are compatible with your bike and then making a final selection based on features and budget.
- Our site allows you to shop by brand, power meter type or price – so have a look around. We have something for everyone
- You can also sign up to receive our Power Meter Buyer’s Guide, which walks you through the buying process step by step
- Or just give us a call! We can discuss your options and figure out what’s best for you
8. The Power Meter City Difference
We would be remiss if we didn’t briefly mention why we think we are best suited to help you with your power meter needs. (We’re biased…but we think we’re pretty great.)
At Power Meter City, we focus on ONE area and one area only: power meters. Unlike others, we don’t deal with other bike parts, clothing, miscellaneous accessories or anything else that can distract us from what we love – yes, power meters!
Our singular focus means we are your power meter specialists – and can offer you the best possible value, selection, advice and service. Here are the top 10 reasons to shop with us:
- Power meter specialists that can provide expert advice and customer service
- The largest selection of power meters and accessories with power meters starting at $259
- Free U.S. and international shipping on most orders
- Fast order processing and same day shipping
- Power meter knowledge center with additional information and resources
- Customer support 7 days a week
- 100% satisfaction guarantee on all orders
- Financing available through PayPal Credit
- 20% off TrainingPeaks Premium with the purchase of a power meter
- 5 star (Excellent) customer service rating on Trustpilot
Well that’s it. Thanks for reading our Beginner’s Guide to Power Meters. Please contact us with any questions!