The best cycling power meter is the one that fits your bike, shoes and riding without creating a new compatibility problem. A technically excellent pedal is the wrong purchase if it uses the wrong cleat. A precise spider is useless if it does not match the crank, chainrings or bottom bracket.
This 2026 guide compares current products using first-party documentation from Favero, Garmin, 4iiii, SRAM/Quarq and Shimano. Roadman's recommendations are editorial choices by use case. They are not claims that Roadman independently laboratory-tested every meter, and temporary retail prices are deliberately excluded.
The short answer
| Your actual constraint | Start here | Why it belongs on the shortlist |
|---|---|---|
| Shimano SPD-SL road cleats | Favero Assioma PRO RS-1 or RS-2 | Current native SPD-SL-compatible pedal; single- and dual-sided options |
| Look Keo road cleats | Favero Assioma PRO RL-1 or RL-2 | Current Look-compatible PRO pedal; single- and dual-sided options |
| Shimano SPD gravel or MTB shoes | Favero Assioma PRO MX-1 or MX-2 | Current SPD-compatible off-road pedal; single- and dual-sided options |
| One sensor system across road and off-road bodies | Garmin Rally 110 or 210 | Removable sensors and separate RS, RK and XC pedal bodies |
| Shimano crank-arm installation | 4iiii PRECISION 3+ or PRECISION 3+ PRO | Single-sided and dual-sided options; Apple Find My; exact crank and clearance checks required |
| Compatible SRAM road crank | SRAM AXS Power Meter Spider or Quarq DZero DUB | Spider-based combined-power measurement within specified SRAM configurations |
| Matching Shimano 12-speed road build | Shimano FC-R9200-P or FC-R8100-P | Integrated rechargeable crankset meter; tied to the Shimano crank configuration |
Do not buy directly from this table. Work through the compatibility order below and open the manufacturer's current product page for the exact model and region before paying.
What “single”, “dual” and “total” actually mean
These labels are often blurred in buying guides.
- Single-sided normally means one side is measured and its contribution is doubled to estimate total power. Favero uses the
-1suffix for its current single-sided PRO pedals; Garmin uses 110; 4iiii PRECISION 3+ is the single-sided crank-arm product. - Dual-sided means both sides are instrumented. Favero uses the
-2suffix; Garmin uses 210; 4iiii adds PRO to the PRECISION 3+ name. - Spider total power measures the combined torque transmitted through the spider. That is a direct total at that measurement point, but it is not the same as two independent left and right sensors.
The old Roadman pages incorrectly called 4iiii PRECISION 3+ dual-sided. The current dual-sided model is PRECISION 3+ PRO, as 4iiii's own product documentation makes clear.
Favero Assioma PRO RS: the Shimano SPD-SL pedal route
Assioma PRO RS is Favero's current road pedal for riders who want native Shimano SPD-SL cleat compatibility. The RS-1 measures the left side and estimates total power; the RS-2 has sensors on both pedals and reports real left-right balance.
Favero states +/-1% accuracy, up to 160 hours of rechargeable battery life, ANT+ and up to three simultaneous Bluetooth connections. The RS-2 specification lists a 10.5 mm stack height, +53 mm Q-factor and compatibility with Shimano SM-SH10, SM-SH11 and SM-SH12 cleats. Those are manufacturer claims, documented on the Assioma PRO RS-2 product page.
Choose RS when remaining on SPD-SL is the primary requirement and moving pedals between road bikes matters. Choose RS-1 to reduce entry cost and preserve an upgrade path; choose RS-2 when actual two-sided measurement is worth paying for.
Favero Assioma PRO RL: the Look Keo route
Assioma PRO RL is the current PRO-generation Look Keo-compatible pedal. As with RS, RL-1 is single-sided and RL-2 is dual-sided. Favero states +/-1% accuracy, automatic calibration, up to 160 hours of rechargeable battery life, a 10.5 mm stack height and +53 mm Q-factor.
The meaningful decision is cleat interface, not a claim that RL produces better training than RS. Choose RL when Look Keo is already the correct fit and you do not want to change shoes or cleats. Favero lists its current specification and serviceable pedal-body design on the Assioma PRO RL page.
The original Assioma UNO and DUO remain listed by Favero as first-generation products. They can still be a rational local-price choice, but buyers should not confuse their external-pod design and 50-hour specification with the current PRO line's spindle-contained design and longer stated battery life.
Favero Assioma PRO MX: the Shimano SPD gravel and MTB route
Assioma PRO MX uses a Shimano SPD-compatible off-road pedal body. MX-1 is single-sided and MX-2 is dual-sided. Favero states +/-1% accuracy, up to 160 hours of rechargeable battery life and a replaceable aluminium pedal body with the electronics protected inside the spindle.
Choose MX for gravel, cyclocross or mountain-bike use when SPD shoes and pedal transfer are the deciding constraints. Do not buy it merely because “pedals are portable”: confirm shoe-cleat compatibility, crank clearance and whether pedal exposure to rock strikes suits your riding. The Assioma PRO MX documentation contains the current fit and specification details.
Garmin Rally 110 and 210: the modular pedal-body route
Garmin launched Rally 110 and Rally 210 in September 2025, replacing the earlier 100 and 200 generation as its current pedal line. Rally 110 is single-sensing; Rally 210 is dual-sensing. Both are sold for Shimano SPD-SL (RS), Look Keo (RK) and Shimano SPD (XC), and Garmin says the removable power sensors can move between compatible road and off-road pedal bodies.
Garmin states +/-1% accuracy, up to 90 hours of rechargeable battery life, quick charging, Travel Mode and Pedal IQ smart-calibration alerts. Rally 210 adds left-right balance and other cycling-dynamics fields. See Garmin's Rally 110 and 210 announcement and the current Rally RS210 product page.
Choose Rally when the removable sensor and multi-body system is genuinely valuable. The older Rally 100 and 200 products may remain at retailers, but a 2026 buyer guide should not present them as Garmin's newest generation.
4iiii PRECISION 3+ and PRECISION 3+ PRO: the Shimano crank-arm route
4iiii's names need exact handling:
- PRECISION 3+ is the single-sided product.
- PRECISION 3+ PRO is the dual-sided product.
The dual-sided PRO uses instrumented left and right crank arms and reports left-right balance, pedal smoothness and torque effectiveness. 4iiii states +/-1% accuracy, up to 550 hours from CR2032 cells, IPX7 water resistance, Apple Find My and a three-year warranty. It offers ride-ready configurations and a factory-install service for selected cranks. The PRECISION 3+ PRO specification and current compatibility list are the sources to check.
Choose PRECISION 3+ when you want a lower-profile single-sided entry on a compatible Shimano crank. Choose PRO only when both crank arms, frame clearance and crank generation match. A left arm with the right length is not enough: check clearance between the sensor pod and frame, and check the exact crank model before ordering.
SRAM AXS and Quarq: the compatible spider route
SRAM's current catalogue includes several power-meter arrangements, so “buy a Quarq” is not a complete recommendation. The AXS Power Meter Spider is a current 107 BCD, 8-bolt direct-mount option for specified RED and Force AXS configurations. SRAM states +/-1.5% accuracy, ANT+ and Bluetooth, IPX7 water resistance and up to 200 hours from a CR2032 battery. Compatibility is explicitly limited by crank and chainring configuration on the AXS Power Meter Spider page.
The Quarq DZero DUB remains current for compatible DZero DUB cranks and many 10- and 11-speed five-bolt chainrings. SRAM states +/-1.5%, MagicZero automatic calibration, 10K temperature compensation and ANT+/Bluetooth connectivity on the DZero DUB page.
Choose the SRAM or Quarq route when the bike is already in the matching ecosystem and a spider is cleaner than changing pedals. Do not infer compatibility from the SRAM logo alone: BCD, direct-mount interface, chainrings, chainline, spindle and bottom bracket all matter.
Shimano FC-R9200-P and FC-R8100-P: integrated road cranksets
Shimano continues to list its Dura-Ace FC-R9200-P and Ultegra FC-R8100-P integrated, rechargeable, dual-sided 12-speed road cranksets. Shimano states less than 1.5% strain-gauge accuracy and more than 226 hours of ride time for FC-R9200-P, with ANT+, Bluetooth LE, active temperature compensation and left-right balance. The current Shimano FC-R9200-P page documents those claims.
Choose an integrated Shimano meter when you already want the matching crankset and chainring configuration. It is not the portable choice: changing bikes or drivetrains means a more involved move than swapping pedals.
Compatibility: check in this order
1. Shoes and cleats
For pedals, identify the actual cleat under the shoe: Shimano SPD-SL, Look Keo and Shimano SPD are different systems. “Road cleat” is not a specification. Changing pedal system can also mean new cleats, setup work and a bike-fit adjustment.
2. Crank and frame clearance
For crank-arm meters, match model, generation and crank length, then perform the maker's clearance check. A pod can contact a wide chainstay even when the crank itself fits.
3. Spider, chainring and bottom bracket
For spiders and integrated cranks, check bolt interface, BCD or direct mount, chainring sizes, speeds, chainline, spindle and bottom bracket. Use the manufacturer's current compatibility map, not an online retailer's category filter.
4. Bike transfer
Pedals are normally easiest to move, but “easy” does not mean careless. Use the maker's torque and installation guidance, set crank length correctly in the app or head unit, and recalibrate if the instructions require it after a move.
5. Head unit and training software
All products above support ANT+ and Bluetooth in some form, but advanced fields and multi-channel behaviour differ. Confirm that the exact head unit or app can record the fields you care about. Do not pay for a metric your display cannot show or your training decisions will not use.
Accuracy, consistency and two devices that disagree
A manufacturer's +/-1% or +/-1.5% figure describes that product under the brand's test protocol. It does not promise agreement with a smart trainer or another meter. Two devices can both sit inside their tolerances and still display different watts. Crank, pedal and trainer measurements also sit at different points in the drivetrain.
Use one source consistently for FTP testing and interval targets. When moving between an indoor trainer and outdoor meter, compare steady efforts under repeatable conditions before creating separate zones. A sudden change, dropout or impossible spike deserves troubleshooting; a stable small difference is not automatically a failed sensor.
The power-meter accuracy troubleshooting guide covers batteries, firmware, crank-length settings, calibration and pairing. The power-meter versus smart-trainer comparison helps decide which device solves the bigger training problem first.
What this guide does not claim
Roadman fact-checked this page on 25 August 2026 against current Favero, Garmin, 4iiii, SRAM/Quarq and Shimano documentation. Manufacturer specifications are labelled and linked. Recommendations are separated from those claims.
The guide does not publish invented failure rates, forum-based allegations, exact lifespan promises or fabricated first-person testing. It also does not claim a particular meter will produce a larger FTP gain: a sensor measures the work; the training plan creates the adaptation. If a model or specification changes, submit the source through the Roadman corrections page.
Turn the watts into training
Once the compatible meter is installed, establish a repeatable baseline with the FTP test tool, calculate current FTP training zones, and use the power-meter training guide to decide which numbers matter.
If you want the plan, review and accountability handled, Not Done Yet group coaching combines a personalised TrainingPeaks plan, weekly review, live group coaching, strength and nutrition guidance, and a private rider community.