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by Dave Rome
August 6, 2020
Photography by Dave Rome
Power meter pedals have been around a fair while, but only in recent years have they got to a point where I’d want them on my own bike. Gone are the separate external pods which make installation tricky, or the bulky pedal bodies ready to scrape the tarmac – now there are a handful of truly classy and reliable options.
One such example is Italian company Favero and its Assioma pedals. I’ve played with these unassuming pedals off and on over the years (they were first released in 2017), but I had never previously spent a huge amount of time on them. And while the accuracy has already been proven by others, I just wanted to know how they functioned as actual, well, pedals.
TL;DR? These things are impressively good.
Much like Garmin Vector 3 or SRM EXAKT power pedals, Favero offers its Assioma pedals with either one-sided or dual-sided power functionality. In either case you get a pair of pedals, but the cheaper Uno (US$425 / AU$640) simply provides measurement on the left only (and doubles the measured power), while the Duo (US664 / AU$1,100) offers a truly independent left and right power measurement. Favero does offer the option to upgrade the Uno pedals to a Duo down the track, but of course, it’s more cost-effective to do so upfront if you’re keen on dual-sided measurement.
Like other power meter pedals, the Assiomas are intended to replace your existing pedals and work with a three-bolt road shoe. The pedal body is made by pedal specialists Xpedo and uses Xpedo’s own “Thrust” cleat, closely based on the Look Keo cleat format. Look Keo cleats do work in the pedal, but provide a subtly different, looser, feel.
Unlike a number of other power meter pedals, the Assiomas fit all the electronics into a factory-fitted small pod that surrounds the external part of the spindle. This isn’t as aesthetically pleasing as fully concealed options from the likes of SRM/Look and Garmin, but it does mean the pedal body, spindle and bearings are effectively no different from a standard pedal. More on this later.
Weight-wise the Assioma Duo is 304 g for the pair; adding cleats (including hardware) brings the total system weight up to 384 g. By comparison, a pair of Keo Max Carbon pedals weigh 312 g with cleats and hardware, while a pair of Shimano Dura-Ace R9100s are 305 g – and neither of those features a dual-sided power meter. A fairer comparison is the Garmin Vector 3, but those are 322 g sans cleats (which are also a Look Keo-type).
The Favero Assioma pedals will connect to the vast majority of GPS cycling computers and smartphones.
The pedals feature both ANT+ and Bluetooth connectivity and are claimed to be within +/- 1% accuracy thanks to a series of eight strain gauges within each pedal pod. Each power meter pedal features its own rechargeable Lithium-Ion battery, which uses a proprietary method for charging. The pedals are said to be entirely waterproof.
Setup, firmware updates, and calibration are all done wirelessly through Favero’s own phone app.
In both cases, the pedals come enclosed in a classy cardboard box with multiple layers to store the number of included accessories.
The pedals arrive well packaged.
Taking up much of the space is the dual USB power adapter, with a handful of common international power outlet plugs provided. Even Australia is covered. The Dual USB adapter works with the provided charging cables, and in the case of my Duo pedal sample, two cables were provided.
The USB cables themselves are each a generous two meters in length so you don’t have to get too creative in how you charge these. At the end of the cable is a unique magnetic induction plug that attaches to the outside pods of the pedals. Just align it with the connection points on the pedal and you’ll feel the magnetic attraction. It’s dead simple.
Favero includes a pair of Xpedo’s Thrust 6º-float grip cleats with a standard three-bolt hole pattern. There are plenty of other cleat options available if you’d like a different float figure.
There’s a handful of steel pedal washers provided, only needed if the plastic power pod touches the crank arm (one washer per pedal will likely be needed for most). And finally, Favero even includes a lengthy 8 mm hex key for install and removal of the pedals. And yes, a paper manual is provided, too.
Ever installed a regular Shimano, Look or similar pedal? Then you already know how to install the Favero Assioma. Favero simply requires you to install the pedals with an 8 mm hex key, and they’re not overly fussy about tightening torque, either. Don’t forget the grease on the threads.
Such a simple process makes these an ideal choice for swapping between bikes. However, you’ll need to pay attention to the clearance between the power pod and your crank arm (and use pedal washers where needed; I needed one per pedal), but that’s pretty much it.
Installation is extremely simple with all the electronics affixed to the exterior of the pedal spindle.
I tend to test electronic devices somewhat blind, and will see how intuitive something is before reaching for the manual. Favero did stump me here — despite the pedals connecting easily to my head unit, they wouldn’t transmit power or cadence figures. That was until I registered them through the company’s phone-based app, something the manual clearly states must be done in order for the pedals to function. I understand the data collection and warranty-based reasons for this approach, but it’s still a little silly.
The setting of crank arm length can be done through either your head unit or via Favero’s app, while the former will handle the zero-reset if you choose. Like many of the latest power meters, these pedals are factory calibrated and automatically adjust to changes in temperature.
Updating the firmware in the pedals (if needed) is quite painless.
And speaking of the app, generally, it was easy and intuitive to use, but I did have an issue with updating the pedal firmware at the start. The firmware has to be updated independently on each pedal, and I hit some snags where it would drop the connection (on an iPhone) between updating the left and right pedals. A couple of phone resets later and I eventually got there. It’s been blissful since.
A power meter is only worth having if it meters power accurately and consistently, and thankfully the Favero Assiomas do just that. From connectivity, to live response rate, to post-ride data, the Favero Assioma pedals gave me no concerns at all.
Whether it was a Garmin, Wahoo, Bryton or Lezyne head unit, the Favero pedals were easily discovered and stayed as such. Likewise, when I put in a strong effort, the figures on my head unit would jump quickly. The left/right balance was equally as fast, and the cadence was always spot on, too.
In addition to all the usual power and cadence metrics, the Assioma’s pedals offer pedal smoothness and torque effectiveness figures (achieved with what Favero calls instantaneous angular velocity measurement, something that also means the Assiomas can be used reliably with oval chainrings). The likes of the Garmin Vector 3 feature some even more detailed measurements, but honestly, I’m yet to meet anyone using such data with purpose.
Favero Assioma next to a Powertap P1.
I’ve ridden plenty of power meters over the years, some great, some problematic, but admittedly testing these things isn’t what I do day in and day out. And so as mentioned at the start of this review, I left the accuracy judgement to others. Ray of DCRainmaker tested the Favero Assioma Duo pedals and found zero issues in the accuracy and repeatability of the data. Since then, YouTube’s GPLama (Shane Miller) often uses these same pedals to benchmark others.
Of course, simply benchmarking one power meter against a handful of others doesn’t ensure absolute accuracy, but short of a lab-based bench test (which we’ve tried to pull off in the past, and continue to look into), these comparative tests are the most trustworthy information we have.
The internal batteries are not at all user-replaceable — in fact, they’re welded in place beneath a waterproof resin filler. However, I don’t believe this will ever be a factor in getting your money’s worth from the pedals. The battery is claimed to last 50 hours of riding between charges and said to retain 80% of its capacity after 500 recharges. And from what I’ve experienced I have no reason to contest these claims.
The pedals use an internal accelerometer to automatically switch themselves on and off with movement. Transporting your bike is likely to keep the little LEDs flashing, and while it’s of little concern for a drive to a nearby event, it’s worth keeping in mind for longer road trips or flights. For this (and reasons of frequency transmission), the app offers a flight mode for the pedals. (Edit: Do note that you’ll need a charging cable in order to wake the pedals up again.)
The pedals are surrounded by flashing LEDs to let you know what’s happening with them. Note the charging plug, it really is simple to install and it’ll simply release if you accidentally trip over the charging cord (don’t ask me how I know this). Another clever feature is that the charging plug is connected to the cable via a Micro-USB interface.
When the pedals do give you a low battery warning, you still have a generous eight hours before they’ll shut themselves off. And as touched upon, charging these pedals couldn’t be simpler with no weak pin connectors or port covers to contend with – just a simple magnetic contact charger. Worth mentioning is that Favero’s charging plug uses a Micro-USB interface, and so you can pack a far smaller cable and/or share it with other devices if you’re travelling.
Ok, so how are they as actual pedals?
It’s a critical question, and in my mind, a power meter pedal is only worth owning if the pedal itself doesn’t introduce compromises. The compromises may have been small with previous pedal-based power meters, but they were certainly present, which kept the door open for crank- and chainring-spider-based power meters to rule the roost.
Ok, so a quick bit of backstory. I used to use Look Keo pedals on my personal bikes before turning to Shimano SPD-SL. At the time, the Keo pedal bodies would suffer surface wear and lead to off-plane rocking at the cleat. And while the French company has fixed this issue with a steel surface plate, many of their pedals eventually suffer from bearing wear that’s not all that easy to solve. I’ve said it multiple times before, but it’s tough to beat Shimano’s offerings when you consider the bearing durability, reliability, ease of walking, and pedal stability.
And so when it came time to test these pedals I had my concerns. Would the power meter pod impact Q-factor? How would the clip-in action be? Would the cleats squeak? And what can be done when the bearings inevitably wear out?
Starting with the first question, the Assioma pedals are wonderfully normal in their form factor and measurements. The pedal width from spindle to centre of the pedal body is 54 mm, something that’s closely comparable to regular Look Keo Carbon and Blade pedals which sit at 53 mm. Shimano R9100 and R8000 pedals are 52mm wide (Shimano also offer models with a 56mm figure).
Up against a Dura-Ace R9000 pedal (previous generation), the Assioma pedal is a little chunkier, but we’re only talking a millimetre or two at the critical points.
The stack is a little trickier and each brand has a different method for measuring theirs. Favero measures it as 10.5 mm from the centre of spindle to where the cleat touches the pedal body. By comparison, Shimano’s lowest stack road pedal (R9100) is 8.8 mm when measured the same way. Now obviously we’re talking about a millimetre here and there, and while that may be a deal-breaker for some, others would never know even if you put a ruler in their hand. The change didn’t bother me.
Favero apparently had issues with some shoes contacting the power pod of its previous pedal system. That issue is fixed with the Assioma pedals.
The cleat-pedal interface is secure and I didn’t miss my Shimanos while spinning circles with the Favero pedals. The Assiomas measure just 4 mm narrower across the pedal body/cleat interface. Likewise, the pedal holds with comforting security, and there’s a good adjustment range to the release tension. And better yet, those Xpedo cleats showed no creaking or squeaking issues on the pedal body surface.
Clipping in is much the same as Look Keo pedals but is a little trickier than what Shimano manages with a larger, deeper hook on the front of the cleat. The free-spinning bearings ensure the pedals hang with the front clip facing up, so it’s at least easy to locate the correct pedal side.
I certainly missed my Shimano cleats once off the bike — whether they’re made by Xpedo, Exustar or Look, the Keo-compatible grip cleats are never as nice to walk in. It’s a complaint that applies to almost all power meter pedals currently on the market.
Pulled apart, the Assioma pedals are simple to service and there are no bushings to cause spindle wear.
No different to the Xpedo NXS pedal, the Assiomas spin on three sealed cartridge bearings which can be replaced if wear occurs. I stripped my pedals down using 6 and 8 mm hex keys, a thin 9 mm socket, and a seal pick. And even that last tool could be subbed for a small flat blade screwdriver. And while they surely won’t last as long, these bearings allow the pedals to spin with even less resistance than well-greased Shimano Dura-Ace pedals.
Most importantly, that servicing can be done cheaply (a kit is US$39) and without any impact to the enclosed power units. This is a key point of difference to some other power meter pedals on the market which either have more detailed service kits and/or need to be returned for such upkeep.
Even better, Favero sells replacement pedal bodies (US$58) if you were to wear out or damage one. And given what that pedal body is, there have been a number of successful reports of people installing SPD-compatible versions of Xpedo’s MTB pedals straight onto Favero’s power-enabled spindles.
I went into this test knowing the Favero Assioma had a proven reputation, but I still had questions of my own. Half a year later I’m impressed that such a technical product can be so simple and reliable to use. So am I buying these to replace my beloved Shimano SPD-SLs? Well, no. I have a few too many pairs of Shimano pedals and a few too many bikes on the go to make a switch to a different cleat platform. I’m sad to be sending these back, but at least for now, this pedal-based power meter isn’t the ideal option for me.
Convinced a pedal-based power meter is right for you? Well, of course, there are other options to consider. Garmin’s Vector 3, Look/SRM EXAKT, and Quarq Powertap P2 are all direct competitors which sell for US$1,000 / AU$1,500, US$1,700 / AU$2,195, and US$899 / AU$1,000 respectively (all dual-sided versions). And while they each have their benefits, many require more difficult servicing, have throw-away batteries to swap on occasion, or need more expensive replacement parts. And picking one of these other options over the Favero only gets more difficult when you consider the prices. As a reminder, the Assioma Duo retails for US$664 / AU$1,100.
The Favero’s external flashing UFO-like power pods may not be to everyone’s aesthetic tastes, but if that doesn’t bother you then it’s hard to do better here.