Originally Posted by
brewer45
The typical 16 gram inflator cartridge puts a 700x23 tire at about 130 psi. We're riding 700x28 Conti Gatoskin tires. Any guess at what the inflation psi from a 16 gram cartridge for a 700x28 tire might be?
I don't use a gauge but I strongly suspect that 130psi in a 23mm tire is pretty optomistic.
I generally pump my 23mm road bike tires up to 110psi. When I have a flat I blow a little air into the inner tube to give it shape, install the tire, and inflate it with 1 full 16 gram cartridge. Subjectively I don't think they are any harder than what I get using my pump and gauge. No way am I getting 130psi.
On my tandem I use 28mm tires. It's been awhile since I had a flat on the tandem, but I use the same 16 gram cartridge. My wife and I aren't the lightest team in the world, but that's enough to get us home without pinch flatting.