My 400ex manual says to run tires at 4.5 psi. I took the air pressure down to 6 and it almost seemed flat. Is this 4.5 psi rating correct for all around off road riding? It seems kind of low. I pressed on the tire at 6psi and almost touched the rim. What psi shouls I be running? I currently have them at 10 all around.

 

I would suspect that your gauge is way off????? What I do is collect all my buddies gauges, and compare them all and come up with an average. If one of them is way off, it is going to be obvious. It is not unusual for gauges to be off by at least 0.5 pounds.

When you are running to high a pressure, you are not taking advantage of the fact that the tires are radials and contribute quite a bit to the suspension/handling of the quad. Lower pressure will also help float you in the soft stuff, but as you pointed out, you don't want to be so soft in rocky terrain that you get a rim pinch.

 

thx. Would you say that a 1/2 lb. or 1lb. over the rated psi would be a good start for all around terrain? Say 5 or 5.5 psi? Will any ordinary air pressure gauge work?

 

You need a low pressure gauge, say 0-15 pounds. Your dealer should carry them.

 

3 to 5 for the soft sand/dirt. 6 to 8 for the hard pack and grass and such.

 

thx re con. i went and got myself a guage and have the tires set at 5 psi. they seem to grip really well now. i like this place. ask and you shall receive.

 

on my ex i run 4.5 pounds in the front all the time but in the back i like to run 3.5 to 4 pounds depending on the terrain.