Favero Assioma Duo vs Pro RS-2

This comparison gets searched a lot and answered badly, because the two products are usually framed as old versus new when the real difference is the cleat. The Assioma Duo is a Look Keo pedal. The Assioma Pro RS is Favero's Shimano SPD-SL pedal. For most riders, that is the entire decision, and everything else — grams, stack, battery hours — is refinement on top of it.

What changed with the Pro platform

Weight and stack.Favero publishes 124.8 g per pedal and a 10.5 mm stack height for the RS-2, and 130 g with the same 10.5 mm stack for the Look Keo RL-2. Both are lighter and lower than the Duo. Stack height matters more than weight here, because stack changes your effective saddle height and a power meter that alters your fit has cost you something to gain a number.

Battery. The Pro range is quoted at up to 160 hours per charge following the firmware update DC Rainmaker reported in February 2026, with a 15-minute fast charge. The Duo is the shortest-running pedal in the line-up. For indoor training this is a convenience rather than a constraint; for long outdoor days and multi-day trips it is the headline improvement.

Measurement range.Favero specifies 0 to 3,000 W and 10 to 250 rpm for the RS-2, plus a 120 kg rider limit in the manual. The accuracy claim itself is unchanged at ±1% from the IAV Power System, which measures real angular velocity through the stroke rather than assuming a constant one.

What did not change: the watts

Both platforms claim ±1% and both use the same measurement principle, so nobody should expect a meaningfully different power number from the upgrade. That is worth saying plainly, because the most common reason people consider this upgrade — "will my data be better" — is the reason least supported by the specifications.

Independent testing of the Pro RS is good but not unanimous. DC Rainmaker found it within a few watts of an Elite Justo 2, around 2 W from a Muov and half a watt apart on a roughly 700 W sprint. road.cc recorded it reading about 5.5% under a SRAM Rival meter across a test period, with steady-state agreement nearer 1.5%. Both findings are real, and together they describe a good meter rather than a perfect one. How accurate are power meters explains why two honest devices never match exactly.

Who should upgrade, and who should not

Upgrade if you are changing cleat system anyway. New shoes, or a move from Keo to SPD-SL, makes the RS-2 the obvious purchase rather than a luxury.

Upgrade if battery format is a real constraint. Long unsupported rides, back-to-back race weekends, or a habit of forgetting to charge things: the 160-hour figure and the 15-minute top-up genuinely change behavior.

Do not upgrade for accuracy. There is no published or independently measured basis for expecting better numbers from the Pro platform than from a healthy Duo.

Do not upgrade for stack height aloneunless you are prepared to re-check your saddle height afterwards — a 2 to 3 mm change at the pedal is a fit change, and treating it as free is how people end up with a new knee niggle and a new power meter in the same month.

If you are cross-shopping outside Favero

The two comparisons worth reading next are Magene P715 vs Favero Assioma, which is the price argument, and Favero Assioma vs Garmin Rally, which is the ecosystem argument. If you are buying mainly for indoor use, our best power meters for Zwift page ranks the whole category on connectivity instead of cleat.