Caution Before performing any work on your Atom Alpha, be sure to also turn off the power system and wear proper protective equipment for electrical components. Tire Pump For transportation purposes, tires are installed partially inflated. Tires must be inflated using a pump with a Schrader valve tip to the recommended 18 – 25 psi (1.24 – 1.72 bar). Natural Tire Size: 20” x 4.25” for the rear and front. Range Power output will vary depending on battery capacity. If your battery is at 20%, for example, it won’t have as much power as a fully charged battery. If your Atom Alpha has been shipped to you along with the battery, please fully charge the battery first. The battery is fully charged when the LED light on the charger is green.