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is it ok to use air rather than nitrogen in the rear shock?

thanks,

p

No

Yes it is. Nitrogen is better, but air (being mostly nitrogen) will work. In the factory service manual for my race bike it says air can be substituted for nitrogen.

This can turn into quite a debate. Many folks say the air will degrade, and introduce moisture, and cause corrosion, etc etc etc. Just as many say you can run air with no problem. It's pretty easy to take the shock by a shop and get it charged with nitrogen, so that's what I'd do.

Air has more gases than just nitrogen and the other gas molecules are smaller, so some of the "air" will leak through the bladder over time (that's why fleet outfits use nitrogen in tires, the pressure stays higher and more constant). Generally speaking, air has a higher moisture and particulate content and will expand more when heated. Most air sources can't provide the 145 lb + pressure needed. Will it work? Yes, but it won't work as well.

When you rebuild a shock, it is customary to precharge the bladder with low pressure air prior to filling the body with oil, then bleeding out the air as you fill - so there is always going to be some residual air in a shock anyway.

Would manufacturers use the more expensive nitrogen if air would work just as well? No.

The MOST I've ever been charged for a nitrogen fill in a shock is $15.

Slick_Nick wrote:The MOST I've ever been charged for a nitrogen fill in a shock is $15.

my last refill this spring cost me about 60$... (at John Deer dealer..)

JoKDX220r wrote:

Slick_Nick wrote:The MOST I've ever been charged for a nitrogen fill in a shock is $15.

my last refill this spring cost me about 60$... (at John Deer dealer..)

Most Deere dealers have a set amount to charge accumulators. Large is one price and small in another. A shock would be a small. At a equipment dealer you are paying a higher labor rate plus materials (nitrogen). Get to be buddys with one of the mechanics and they will probably do it for you on their lunch break.

Where are you located?

New York. Up by Vermont.

I know on my bike after a HARD ride of enen 30 mins or so the rear reservoir is too hot to touch. You should feel the KX after a moto! And you want to run just air?

Oh well, no driving over to the house for a free charge.