The power-sensing spindles transfer between Rally body types through Garmin's conversion kit system. Buy Rally RS bodies for Shimano SPD-SL or Rally XC bodies for Shimano SPD mountain use, then move the spindles between platforms as your riding changes. The measurement electronics live in the spindles, not the pedal bodies. If you ride both road and mountain bikes, or switch between road racing and cyclocross seasonally, you can move the same dual-sensing spindles across different cleat systems without buying multiple power meters. The RK200 spindles also work in older Vector 3 pedal bodies if you're upgrading from that system.

Accuracy measures plus or minus 1 percent, which matches hub and crank-based power meters. Both pedals support field calibration through your Edge computer or compatible head unit. Zero the system before rides to account for temperature changes that affect strain gauge readings. The left pedal communicates with the right pedal, then the left pedal transmits combined data to your head unit. If you're running the pedals on a trainer, make sure both pedals wake up before starting your workout so the trainer sees total power rather than just left-leg data.

ANT+ and Bluetooth connectivity works with Edge cycling computers, Garmin watches, and third-party head units that support power meter protocols. The system syncs to Garmin Connect for long-term analysis and tracking trends in your cycling dynamics data over weeks and months. Data transfers to TrainingPeaks, Strava, TrainerRoad, and other platforms. Tacx desktop app support means you can use the pedals with compatible smart trainers for indoor training. Some trainers let you compare pedal-based power against the trainer's internal power measurement for consistency checking.

Battery life runs up to 120 hours on either 4 LR44/SR44 button cells or 2 CR1/3N batteries per pedal. Garmin recommends CR1/3N batteries as the primary option for Rally. Each pedal has its own battery compartment with threaded metal inserts for durable cap attachment. You can replace batteries roadside with the included tool or a coin. The caps feature improved contacts compared to Vector 3 pedals. IPX7 water resistance handles rain, puddles, and pressure washing without affecting the electronics.

The 53mm Q-factor matches standard road pedals. Included 2mm washers bump Q-factor to 55mm if you need wider stance. Stack height measures 12.2mm, which provides ground clearance for cornering. The 105-kilogram maximum rider weight accommodates most cyclists. Installation uses a standard 15mm pedal wrench with recommended torque of 34 newton-meters, which runs slightly higher than typical pedal installation torque but doesn't affect power measurement accuracy. The complete pedal pair weighs 326 grams.