I typically keep one CO2 on the bike. It is nice to have one there for the quickie fix.
My frame pump is a 2 stage pump. It is a Blackburn Mammoth 2-stage. At the butt end it has a switch for low pressure/high volume and high pressure/low volume. It moves a lot of air on the low setting, which is great for MTB tires, then you can set it to high and add the pressure. You do have to set it up for presta/schrader valves. Where the nozzle is, you just unscrew it, and there are two pieces inside. You dump those out and flip both. It is really easy once you see it. I love the thing. I wouldn't mind one of those pumps with the flex line and foot tab, but the Blackburn is nice, compact, and light.
http://www.blackburndesign.com/pumps...l#.UfXOIW03Hvw
I've also been looking at replacing it with this one. The flip out handle would be nice to have:
http://www.blackburndesign.com/pumps...l#.UfXOe203Hvw
Oh, and BOTH have internals that can be rebuilt....which rocks.
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