Honda TRX400X 2009 Owner's Manual page 143

Air Pressure
Refer to Saf ety Precautions
Properly inflated tires provide the best combination of handling, tread
life, and riding comfort. Generally, underinflated tires wear unevenly,
adversely affect handling, and are more likely to fail from being
overheated. Overinflated tires make your ATV ride harshly, are more
prone to damage from surface hazards, and wear unevenly.
Make sure the valve stem caps are secure. If necessary, install new caps.
Always check air pressure when your tires are ''cold.'' If you check air
pressure when your tires are ''warm'' even if your ATV has only been
ridden for a few miles the readings will be higher. If you let air out of
warm tires to match the recommended cold tire pressures, the tires will
be underinflated. Be sure to check tire pressure at the riding site, since
changes in altitude can affect air pressure.
The recommended ''cold'' tire pressures are:
RECOMMENDED
PRESSURE
on page 77
−
FRONT
4.0 psi (27.5 kPa)
.
−
4.0 psi (27.5 kPa)
Servicing Your Honda
Tires
REAR
135