recently bought Innovations ultraflate pro inflator. anyone know the best place to purchase new cartridges? thanks

How often do you flat?

If you have fairly frequent flat tires, buy the 12 gram cartridges in bulk from Wall Mart because they're lots cheaper. If you only flat once or twice a year, buy the 16 gram threaded cartridges from a bike store because they're more convenient to use. Whichever you choose, I'd advise practicing at least once at home before you ride farther away from your car than you're comfortable walking back.

my ultraflate works well. i keep 3 16g cartridges in my pack along with an extra tube and patch kit. i use them so rarely, the cost difference between the 12g and 16 does not really matter to me. like the grouch says, it pays to practice before you need it ...

-- michael

In the US, sporting goods stores that sell pellet guns or paintball guns sell 12g CO2 cartridges in bulk. Stores like Walmart or Kmart would be the cheapest. Since you used the British spelling for tires (tyres) I assume you are not in the US so substitute whatever big box stores you have.

Oh, if you are using threaded cartridges without a cover, be sure not to grip the cartridge with your bare fingers when you inflate the tyre. As the gas depressurizes into the tyre, the CO2 cartridge will drop temperature rapidly. I gave myself a minor case of frostbite a couple weeks ago by forgetting about this. Everything is OK, but the skin was sensitive for several days.

I bought a foam sleeve to put over my 16g cartridges from now on.

The Ultra supposedly takes 12 gm unthreaded cartridges. Head over to Wally-World or any other big box store and get em back in the sporting goods section (air rifles and thier brethern).

I just picked up a box of 25 for $8.