2019 Honda TRX420FA6 ED — Owner's Manual
You can select the desired shift mode with the drive mode select switch. The transmission automatically shifts to keep the engine at the best speed for the riding condition. Release the rear brake lever/parking brake lever and increase engine speed by gradually opening the throttle.
Remember to close the throttle each time you shift to the next lower gear. Learn the relationship between engine sound and the normal shifting points. Make sure there are no obstacles or people behind you before selecting reverse gear.
Carefully apply both the front and rear brakes when stopping in reverse gear. The single disc brake of the rear drivetrain is hydraulically activated by pressing down on the brake pedal and mechanically activated by operating the rear brake lever/parking brake lever. Continuous brake application can overheat the brakes and reduce their effectiveness.