Best Power Meter
“What is the Best Power Meter?” you ask. The clear winner of The Best Power Meter is…
There is no single best power meter for everybody.
There are now many options, some of which may be suitable for the precise need you have. You might have a need based on a certain kind of bike; a certain price range; a certain level of required accuracy; a certain bike-related sport; and so on.
I’ll cover the main kinds of need as I see them, hopefully, that will match your personal circumstances and, if not, at least you will be pointed in the right direction for further research or, perhaps, I will confirm your suspicions. Then there are Eu/UK/USA links to 3 leading power meter resellers where you can compare prices (wiggle.com and powermetercity.com).
Once an expensive add-on for highly serious cyclists, the power meter has now gone mainstream with many affordable options.
Whilst someone new to cycling might well have heard of Giant or Trek or Specialized as bike manufacturers, it’s unlikely they will have heard of Powertap or Favero or SRM. Generally, power meter manufacturers are specialist companies, although that is gradually changing with, for example, Garmin getting in the game a few years ago.
CURRENT STATE OF AFFAIRS
The market for bike power meters is growing with new products and new entrants emerging regularly. These themes are also emerging:
- Accuracy – generally ‘good‘
- Ease of Installation – from simple to complex
- Price – from a couple of hundred to a couple of thousand Eu/$/GBP…most prices adjusting downwards as time passes.
- Consolidation of features – ANT+ & BLE/BTLE, single-sided and dual-sided, calibration, battery type & performance, cadence and other peripheral metrics.
- Durability/Serviceability – not widely appreciated. Changing a battery or bearing or even the initial installation might require your power meter to be sent away.
- Customer Service – generally good.
FUTURE OF THE BEST POWER METER
More and more of you will buy a power meter. Many of you will buy more than one. Sales growth will continue.
There are now running power meters (STRYD and others).
In terms of the bike side of the power meter market, we will see yet more new entrants. For example, Specialized entered the market in 2018 and Shimano are also a recent entrant, possibly with a revised 2020 model. I don’t think we will see too many more novel, technical solutions and I believe we will also see continuing downward pressure on prices below 2017 levels.
The Best Power Meter for Who?
Josh at powermetercity.com and Bob at cyclepowermeters.com cogitated over their ‘Best Power Meter‘ lists and made their recommendations. I took the best of their knowledge and combined it with my own to produce these recommendations. Three people’s views must be better than one?
Just to be clear the recommendations below are mine. I may well have ignored the far more intelligent advice proffered by Josh or Bob. I’ll take the blame 😉
On A Budget – WatTeam PowerBeat (single)
WatTeam have stopped trading
Alternative: ‘conventional, budget solution’: 4iiii 105’s or Stages G3 105’s these should come in below $/£/Eu400.
Don’t be afraid of single-sided power. You can spend some time researching dual-sided solutions and problems exist there with accuracy too. A single-sided PM is a good solution as a first foray into power and 4iiii and Stages will give you a good, consistent product which you WILL be able to benefit from. Changing a crank from bike to bike is probably about as easy as swapping over two pedals.
ESSENTIAL READING: Stages G3 Review
Cheaper ‘novel’ alternatives exist: Consider PowerPod (ANT+/BLE) or Powertap Powercal
Multi-Bike Owner – Favero ASSIOMA (duo)
Alternative: PowerTap P1 or Garmin Vector 3
Think of the words ‘universality’ or ‘swapability’ and pedals become the solution. The ASSIOMA wins on price and the 50-hour battery life of its rechargeable battery is not an issue for me. Garmin’s Vector 3 is a comparable format now that the pods have gone from the Vector 2 but some might say the PowerTap P2s are a little on the large and heavy side. Q1.Q2.2018 are seeing issues with Vector 3.
- ASSIOMA – lightest, cheapest. the only one of the 3 with a 50-hour rechargeable battery. In 2018 a firmware upgrade gave market-leading 1% claimed accuracy (99%)
- VECTOR 3 – equally as expensive as the P1. Extra Garmin metrics (PCO/PP). The manufacturer stated accuracy is the same as ASSIOMA.
- P2 – heaviest, generally equally as expensive as the Vector 3. Probably as accurate as the other two. Supports elliptical chainrings. Extra pedal metrics for Powertap app.
PRICE GUIDE: $519 or £449 less 10% with code the5krunner10
Power Meter Newbie – STAGES Dual
Alternative: 4iiii Crank (single sided) or ASSIOMA Pedal (single sided)
You want a competent solution without risking too much on the price front. The many Power Meter Newbies that came before you seemed to mostly buy Stages or Assioma/bePRO. Take the path well-trodden and do the same but also consider 4iiii on your cranks.
Also, consider that Stages are linked to Team SKY and that association may have swayed some people more than the technology warranted.
PRICE GUIDE: from $400 (sale) or £449 less 10% with code “the5krunner10”
Image source: stagescycling.com
Accuracy Seeker – PowerTap
Alternative: Quarq, and maybe SRM, Verve Infocrank or Pioneer Power but surely not Garmin?
“..current power meters used by elite and recreational cyclists vary considerably in their trueness; precision is generally high but differs between manufacturers. Calibrating and adjusting the trueness of every power meter against a first principle-based reference is advised for accurate measurements.” Source: Maier et Al.
Also, consider drivetrain losses which could be 2%. If you do then you may well settle on the PowerTap hub for accuracy. That seems to be what Alphamantis (bought by Garmin) did for their aero testing services.
Also, consider that Garmin’s Vector 3 claims +/-1% accuracy – higher than the claimed accuracy of either the Powertap G3 or P1 (+/-1.5%). That’s either inconvenient for our power meter accuracy beliefs … or wrong. April 2018 saw a firmware update for Favero’s ASSIOMA which now also delivers a claimed accuracy of +/-1%
Then we come on to crank-based power meters, where the right-side can introduce notable inaccuracies for certain designs. These inaccuracies can be ‘estimated out’ with fudge factors. I like fudge but perhaps not on my bike.
The Verve Infocrank also deserves a special mention. It was built from the ground up as a power measuring device.
2017-18 PRICE GUIDE: hubs from $499 or £599 less 10% with code “the5krunner10”
Mountain Biker – SRM 2x, 3x
Alternatives: 1x Quarq, 2x/3x – Stages, 4iiii or INPower REX
SRM is probably the Best Power Meter option for 2x and 3x setups but they are expensive.
Consider that potentially higher torques in MTB riding might not favour single-sided solutions. But, as you probably already know, your choice is somewhat limited by a relative lack of competing products in the MTB space.
PRICE GUIDE: SRAM X01 from $1400 less 10% with code the5krunner10 & 4iiii Precision Shimano XT M800 from £469 less 10% with code the5krunner10
Multi-Location Buyer – PowerTap
You want to use different kinds of power meter locations and want the results to be comparable. I would say it was a reasonable assumption that products coming out of PowerTap’s testing labs will have been built to similar tolerances.
Go for PowerTap’s hub, chainring and pedal solutions.
2017-18 PRICE GUIDE: hubs from $499 & £599 less 10% with code “the5krunner10”
Elliptical / Oval Chainring Owner – PowerTap P1
Alternatives: ROTOR 2INpower or a hub-based solution or Favero ASSIOMA
Your sister’s Garmin Vector 3s or your mate’s STAGES cranks will give incorrect readings with oval (elliptical) chainrings. The P1’s more frequent measurements and algorithms make them more accurate with elliptical chainrings. Of course, if you measured the power elsewhere, such as the hub, then you won’t have the elliptical chainring problem.
Also of note is that April’s new firmware from Favero for their ASSIOMA pedals now supports a different measurement algorithm that supports elliptical chainrings.
I like ROTOR’s 2INpower solution too.
2017-18 PRICE GUIDE: P1s from $599 & £550 less 10% with code “the5krunner10”
Time Trialist – Quarq
Alternative: Anything dual-sided and crank-based such as the 4iiii Precision Dual
Accuracy, precision, repeatability are key. You will probably be buying another Quarq to go with the one you already have on your other TT bike. This one will not be swapped between bikes either. You like the self-calibration offered by the Qalvin app.
PRICE GUIDE: 4iiii for Shimano 105 5800 from $399 less 10% with code the5krunner10 & Quarq DZero spider from £575. Remember that 4iiii’s stated accuracy is +/- 1%
The De-Risker – Garmin Vector 3
Alternatives: SRM and Stages are the only alternatives who also have their own head units.
If all your products come from the same manufacturer then the manufacturer cannot blame anyone else (other than you) when things stop working. As you own a lot of their other products you are more likely to get better treatment. Peripheral metrics like ‘Platform Centre Offset‘ will also work for you!
The DIY-Avoider – Favero ASSIOMA
Alternative: hub-based solution
You change the ASSIOMA as easily as you would any other pedal. It is that simple. ASSIOMA comes with a rather large hex wrench (Allen key) and you do it up ‘fairly tightly’. You’re good-to-go. Even you can do that 😉
The same can be said of the PowerTap P1 and Garmin Vector 3..but the ASSIOMA is cheaper with no other downside.
You could probably swap out a wheel easily enough as well. Either that or you get a lift home whenever you get a flat tire/tyre, which I suspect is unlikely. However, we both know that you aren’t going to take off the cranks yourself despite being told it’s usually really easy. Go forth and buy a pedal solution.
PRICE GUIDE: $519 & £449 less 10% with code “the5krunner10”
Commuter – PowerPod
Alternative: Powertap Powercal
For this Best Power Meter category, I’m envisaging a commuter who also trains and sees commuting as a great way of putting the miles in. Perhaps accuracy is not at all important and the ride to work is just a case of recording the (approximate) watts as you draft behind vehicles and regularly change riding position. You use the power you recorded as an input to training load calculations.
Perhaps also there is a risk of any visible power meter attracting unwanted attention from thieves. The PowerPod would meet this scenario as it is EVEN easier to remove than your rear wheel or pedals…it’s unscrewing one bolt. If the PowerPod gets stolen it’s cheap(ish) to replace.
For the STRAVA segment hunters amongst you commuters then more accuracy might be important. Most single-sided cranks should be good for your purposes and you can use some sort of abrasive paper (emery) to de-badge & disguise the crank.
ESSENTIAL READING: Velocomp PowerPod Review
PRICE GUIDE: $299 less 10% with code the5krunner10
On An Indoor Trainer
Your regular power meter will most likely also work if you put your bike on a cheap indoor trainer that just applies resistance to your back wheel.
I use a Wahoo KICKR (review) but you don’t have to go to that expense AT ALL for your winter of power training. Smart trainers like the KICKR are pretty cool and have lots of ‘extra’ features. If you have £/$/Eu1000 to blow then go for it.
But if you don’t…
With an ANT+ dongle and a bit of research with Mr Google, you could quite easily find an indoor power solution for the winter for about $/Eu/£10.
The next cheapest approach is to buy ‘any old non-smart resistance trainer’ but then use power meter pedals or cranks. the advantage also being that the same power meter can be used outside too. #DataConsistency.
SMART Trainer code for 10% discount – “the5krunner10” (selected models)
The Best Power Meter Pedals
I didn’t want to include a product type but many people are going for the pedal option and this separate post looks in much more detail at the best power meter pedals. Pedals are pretty accurate now and easily switched between bikes (although switching a crankset is potentially nearly equally as easy)
The Best Power Meter For Me
I compete in Age Group Duathlons and Triathlons to a reasonable level and an occasionally good level at some point in the dim and distant past. I have lots of aero kit to help me pretend that I can do TTs as well as real cyclists (I can’t). I love my weekend cycling as much as anyone else, except when I am staring at some ‘young gun’ flying off up a very steep hill.
Total power or dual power is best for me as I have an asymmetry and I also look for a reasonable-to-good level of accuracy & consistency
I don’t like wasting hours of my life tinkering at bike mechanics. I want to swap my main power meter regularly across 3 bikes and so I use Favero Assioma Duo to collect ALL my data for me. I have ZERO issues with them. Even with the previous Favero bePRO, I had very, very few issues over a couple of years other than the slight faff of changing bikes. The ASSIOMAs are more than accurate enough and for me (stated accuracy 1%), as were the bePROs that came before them. My next purchase will be a PowerTap G3-based rear wheel of some sort. That’s me. Now you know.
I use other, varied kit to collect data for ‘the5krunner.com’. The5krunner, unfortunately, needs N+1 bikes and Y+1 power meters.
Issues – aka Things to Worry About
Just when you had made your mind up these spanners are thrown into the works:
- PROVEN – All the power meters mentioned above are ‘proven’ in the sense that they are well established and are generally ‘known quantities’. New Power meters like 4iiii Podiiiium probably don’t yet meet the ‘proven’ characteristic but will most likely be perfectly fine.
- Direct Force Measurement or Opposing Force Measurement and the accuracy of doubling up a single-sided measurement – PowerPod would argue “If you want accuracy why would a necessarily asymmetric rider measure power on one side and double it?“. They would argue that their power meter relatively accurately measures total power if your aerodynamic constraints don’t change too much. They might also point out that asymmetries change as you fatigue.
- Single-sided or dual-sided – go for dual-sided or total power measurement if you can afford it, don’t worry too much if you can’t.
- I’m not a bike mechanic but I am highly competent in other DIY fields (if I may say so myself) yet some power meters are a time-consuming PITA for me to install on bikes. Unless you have a combination of tools+time either buy a simple-to-install solution or pay for someone else to do it for you.
- Daily calibration is required with some power meters to ensure their potential accuracy is delivered. (It’s simple)
- Surface conditions and temperature may well affect accuracy (don’t worry too much)
- Durability – Some power meters are not designed to take knocks. All power meters need to keep water out. (They are all good for the road)
- Battery Life – A rechargeable battery giving 30-50 hours of use seems good enough to meet the ‘Best Power Meter’ criteria. But don’t forget, there are options that exist to give you months of usage from a replaceable AAA battery or CR2032 if you are specifically concerned about battery life.
- Crankset – 4iiii tend to focus on Shimano cranks whereas STAGES offer more crank options.
- Used – I might consider a nearly new Power Meter from a friend but I wouldn’t buy one secondhand. You might take some comfort from a manufacturer-refurbished power meter on special offer…or not.
- Accurate or consistent for Jo Average? – Obviously, a consistently accurate product is best 😉 You can compare the data from one consistently accurate power meter to another consistently accurate power meter within the constraints of the stated/actual accuracies of each. But if you only have one, consistent power meter then I reckon that’s OK… don’t worry about it too much unless you have more than one power meter. Don’t worry too much about ‘your old data becoming meaningless‘ when you buy a new power meter. Hopefully, you’ll be improving your power levels year-on-year so I don’t reckon that old data will be any use to most of you and, even if it was, I bet you would never look at it 😉 FWIW: I work on power zones broadly defined from my last 3 months’ worth of efforts.
- A rear wheel, hub-based power meter is pretty much fixed to that wheel so what do you do for power when you get your disc wheel out on race day? What if discs are banned on race-day due to the wind? What if your ITU draft-legal race requires wheels to have spokes? If you are considering a hub-based solution then YOUR Best Power Meter solution is very likely to involve more than one power meter type OR two or 3 power meter hubs.
- Cleats – each power meter pedal brand requires some flavour of XPEDO/LOOK KEO cleat. If you don’t like those cleats then you have to consider a non-pedal solution. Sorry.
- Mountain bikes – buy a product specifically designed for that usage. Although easy trail riding with power meter pedals may well be occasionally fine ie where you won’t fall off or bang into something very hard. You might find that trail riding can produce massive power spikes as the bike bangs around…my record is over 2000w in that scenario. If only it were true.
- Other metrics – most power meters will also produce cadence. Some power meters produce other metrics linked to the efficiency of your pedal stroke or application of force to the pedal. Cadence is useful and actionable, the other metrics ‘less so’. Don’t worry about those ‘other metrics’ unless you have a VERY specific need.
Best Power Meter – RECOMMENDATION
For 80% of cyclists I just can’t see any reason why you would not buy the Favero ASSIOMA power meter pedal solution. It really is a no-brainer…IF you can afford it.
If you cannot afford the ASSIOMA DUO then the next sensible option would be a single-sided ASSIOMA. Then below that would be a crank-based system from STAGES or 4iiii.
If that’s still too expensive for you then you are in the realms of a POWERPOD or just simply training by heart rate.