# Stages Power LR Shimano Ultegra R8100 vs Magene P505: specs and price compared

A sourced, side-by-side comparison of the Stages Power LR Shimano Ultegra R8100 (Stages) and Magene P505 (Magene) among cycling power meters. Magene P505 is the cheaper of the two at $349.

## Side by side

| Spec | Stages Power LR Shimano Ultegra R8100 | Magene P505 |
| --- | --- | --- |
| US price | $864.99 | $349 |
| Brand | Stages | Magene |
| Mount type | crank-arm | spider |
| Measurement sides | dual-sided | — |
| Accuracy pct | 1.5 | 1 |
| Weight grams | 15 | — |
| Battery type | CR2032 | rechargeable-liion |
| Battery life hrs | 175 | 200 |
| Connectivity | ANT+/BLE | ANT+/BLE |
| Power balance measured | Yes | No |
| Cycling dynamics | — | No |
| Waterproof rating | IPX7 | IPX7 |
| Warranty years | — | 2 |

## Key differences

- Mount type: Stages Power LR Shimano Ultegra R8100 crank-arm vs Magene P505 spider
- Accuracy pct: Stages Power LR Shimano Ultegra R8100 1.5 vs Magene P505 1
- Battery type: Stages Power LR Shimano Ultegra R8100 CR2032 vs Magene P505 rechargeable-liion
- Battery life hrs: Stages Power LR Shimano Ultegra R8100 175 vs Magene P505 200
- Power balance measured: Stages Power LR Shimano Ultegra R8100 Yes vs Magene P505 No

## Sources

- Stages Power LR Shimano Ultegra R8100: https://stagescycling.com/en_us/stages-power-lr-shimano-ultegra-r8100-dual-sided-power-meter (stagescycling.com, verified 2026-07-13)
- Magene P505: https://www.magene.com/en/power-meters/58-p505-spider-based-power-meter.html (magene.com, verified 2026-07-13)

Canonical: https://frontdeskreview.com/gear/cycling-power-meters/stages-power-lr-ultegra-r8100-vs-magene-p505/
Cite: Per The Front Desk Review, Stages Power LR Shimano Ultegra R8100 ($864.99) vs Magene P505 ($349) — sourced spec-by-spec comparison at https://frontdeskreview.com/gear/cycling-power-meters/stages-power-lr-ultegra-r8100-vs-magene-p505/
License: CC BY 4.0.