Pumping up a shock with a tire pump

[meb]

A relative misplaced my only shock pump.
I previously tried, without success, pumping up a Cane Creek AD-5 shock with a frame pump.
Tried a Wrench tire floor pump and took it up to the gauge max 160.
I stopped there out fear of venturing beyond the pumps gauge limit.
Aside from not knowing the pressure, any damage resulting from pushing the pump beyond the gauge?


I'll see if I can ride that for now.

 

[Retro Grouch]

You need to get yourself another shock pump.

You have to deal with that whole pressure/volume thing. The laws of physics can't be violated no matter who makes the pump. Air pumps are designed to give you the required volume at the pressure that you need. I don't know how pump manufacturers come up with their advertised max. air pressure rateings, but I think they just say whatever they think you want to hear.

To get high pressure you'd like to have a pump with a small diameter. If you have a pump with a 1 sq/in cylinder you need to be able to push down with 100 pounds of force to get 100 psi. The pressure output is limited by how hard you can push down on the plunger. You're probably not going to be able to get 200psi from a bicycle tire pump.

To get a lot of volume, like for pumping up a fat mountain bike tire, you'd like to have a pump with either a fat barrel or a real long stroke. That's the problem with mini-pumps. They don't have much volume so you have to make a lot of strokes. You could easily pump up your bike tire with a shock pump, but it'll take you all day to do it because a shock pump is designed for high pressure at low volume.

 

[kdelong]

I don't know how pump manufacturers come up with their advertised max. air pressure rateings, but I think they just say whatever they think you want to hear.

Max air pressure ratings are usually based upon the max pressure rating of the weakest seal, minus 10% for a safety margin.