Favero Assioma vs Garmin Rally

These are the two pedal-based power meters an upgrading rider actually chooses between, and the comparison is unusually clean because the headline specification is a tie. Both claim ±1% accuracy. Both measure each leg independently in their dual-sided versions. Both install with a pedal wrench and move between bikes in minutes. So the decision comes down to three practical questions: which cleats you ride, how you feel about batteries, and how much the ecosystem matters.

Cleats: the question that decides most purchases

The Assioma is a Look Keo pedal and always will be. If you already ride Keo, this is a non-issue and the value argument runs unopposed. If you ride Shimano SPD-SL, adopting the Assioma means new cleats on every pair of road shoes and re-learning a slightly different float and release feel. That is not a disaster, but it is a real cost and a real annoyance.

The Rally's convertible design is the genuinely unique feature in this category. Because the electronics live in the spindle, Garmin sells body conversion kits that turn an RS (SPD-SL) pedal into an RK (Keo) or an XC (SPD) pedal. For a rider who might buy a gravel bike next year, that is real optionality — you keep the power meter and change the interface.

Batteries: recharge or replace

Favero uses a sealed rechargeable cell in each pedal with a magnetic charging dock, quoting around 50 hours per charge. There is no battery door, nothing to cross-thread, and nothing to buy. The routine is: ride until it warns you, dock overnight, forget again.

Garmin uses replaceable coin cells, quoting around 120 hours per set. Longer life, no charging cable, and the ability to fix a dead pedal on a Saturday morning with a battery from a supermarket. The trade is a battery compartment with a seal and a torque spec that has to be respected — historically the part of pedal power meters people most often get wrong.

Neither approach is better in the abstract. Rechargeable suits riders who like fewer consumables; replaceable suits riders who travel and would rather carry a spare cell than a charger.

Ecosystem and data

Both broadcast standard power over Bluetooth and ANT+, so both work with Zwift, TrainerRoad, Wahoo head units and everything else. If your world is standard, this section changes nothing.

Where Garmin pulls ahead is the extras. Rally pedals report cycling dynamics — seated versus standing time, platform center offset, power phase — which appear automatically on a Garmin Edge or Forerunner. Our honest read is that these metrics are interesting rather than actionable for most riders. Very few people change their training on the basis of platform center offset. If you are working with a fitter or a coach who asks for them, they matter; if not, do not pay for them.

Single-sided versions

Both platforms have a cheaper single-sided model, and for most riders that is the smarter purchase. The Assioma Uno and the Garmin Rally RS100 and RK100 measure the left leg and double it — which tracks change over a training block just as reliably as a dual-sided meter, because your imbalance is usually small and stable.

Favero's single-sided route has one extra advantage: you can buy the second pedal later and convert the Uno into a Duo. If you are unsure whether you want balance data, starting single-sided and upgrading is the lowest-regret path. Our budget power meter roundup covers that ladder in full.

Which is more reliable?

We do not run long-term durability tests and will not pretend otherwise. What we can say is that both platforms have been on the market long enough to have a public record, both come from manufacturers that honor warranties and ship firmware fixes, and both use sealed spindle electronics that survive weather. The single most common source of trouble on any pedal power meter is installation — under-torqued or over-torqued pedals, and on the Garmin, battery doors. Follow the torque spec and both will be fine.

The verdict

The Assioma Duo is the better buy for most riders. Identical accuracy claim, fewer consumables, less money. Unless something on this page describes you specifically, that is the pedal to get, and the saving is real enough to fund a serious fan or a season of Zwift.

The Garmin Rally is the better buy in three cases: you are committed to SPD-SL, you want the option to move to SPD for off-road riding, or your training life runs through a Garmin head unit and you value that integration. In those cases the premium buys something specific, which is exactly when a premium is worth paying.