Originally Posted by
DannoXYZ
4. use larger tyres at lower-pressures. For your 350lb load, I'd recommend at least 28mm tyres, 32-35mm would be best at 85-90psi. The lower pressure absorbs more road-shock with better damping, thus reducing peak-G forces on the wheel when hitting any kind of road irregularity.
Actually larger higher pressure tires are better for weight bearing.