For a more effortless and secure experience on our site, please consider updating your browser

What to Do With CO2

June 21, 2016
What to Do With CO2

The arrival of CO2 cartridges has meant that flats can be fixed so much faster than can be done with a hand pump. We step you through how to use a CO2 so you can get back in the saddle in no time.

What you will need

  • New tube

  • CO2 cartridge

  • CO2 inflator

How to use CO2 cartridge to inflate your bike tyre

Threaded or non-threaded

As the name suggests CO2 cartridges are either threaded or non-threaded. The threaded cartridges screw onto the inflator head whereas the non-threaded CO2 cartridges simply push on. Make sure when you purchase CO2 cartridges that they match the inflator. There's not much point having a screw-on CO2 inflator with a threaded CO2 cartridge, or vice versa.

See here: To shop Everything Bike

Flow control?

Some CO2 inflators and pumps have flow control. This is obviously very handy as you can moderate the amount of CO2 released into the tube and prevent the tube over inflating. Others will not have this option and it is a case of all or nothing.


Put some air into your tube before placing it onto the wheel. This will give the tube some shape before you put attempt to put it into the wheel. You can either blow into it like a balloon, or if you have a flow control CO2 inflator you can let a little put a little bit of air in... although this is risky because if you get it wrong, there's a CO2 cartridge finished.

It's very important at this point that there is no sign of the tube. If there is any part of the tube outside of the tyre, it will expand and bulge as it inflates and almost certainly pop. If it doesn't happen straight away, it definitely will once you start riding.

Depending on which type of inflator you have, you may need to screw on the CO2 cartridge before putting the inflator on the tube valve or vice versa.

Some inflators require you to screw the CO2 cartridge to the inflator and then press into the inflator head to release the CO2. Others will release the CO2 as soon as you screw on the CO2 cartridge. Make sure you check which inflator you have and use accordingly.

Let the magic happen

Make sure you have the inflator head firmly on the valve before either pressing the inflator head or screwing on the CO2 cartridge.

  • Once the CO2 is released the CO2 Cartridge and inflator head will get extremely cold, so it pays to wear gloves or buy CO2 cartridges with protective sleeves to prevent you from burning your fingers.

The inflation process will happen very quickly, within 1-2 seconds. Another reason to make sure the inflator head is secured. The tyre pressure each CO2 cartridge can achieve will vary depending on the size of the cartridge and how well the user performs. You can expect to easily reach 100psi with a 16g CO2 cartridge.

  • CO2 cartridges normally come in 12g, 16g, 20g and 25g sizes.

You may have to moderate the amount of CO2 you release into the tube. The bigger cartridges can over-inflate and cause the tube to burst. As you inflate the tube, be sure to keep contact with the tyre, and a watchful eye. Once it is firm, it's time to stop inflating.

  • It's hard to know exactly how much inflation is too much when doing it by touch or sight, but the more you do it, the easier it will become to know when it's at the desired pressure.

  • Once you've finished pumping up your tyre, remove the empty CO2 cartridge from the CO2 inflator and either place it in your jersey pocket or put it in the nearest bin. Don't leave it on the side of the road for someone else to pick up.

The next day

You'll more than likely find that your tyre will be flat (or well on its way to being flat) within 24 hours because CO2 will leak out of your tyre faster than air. So don't forget to pump it up before your next ride.

See here:For more great advice, reviews, guides and news, head this way


CO2 cartridge - Small metal containers of compressed CO2.

CO2 inflator - Tool that attaches to the tube valve and pumps up a tube / tyre. CO2 cartridges will either screw onto the CO2 inflator or press into them to release CO2.

PSI - Unit of measurement for pressure. Measured in 'Pounds per Square Inch'.

Follow BikeExchange: Email | Facebook | Twitter | Instagram | YouTube | STRAVA

Subscribe to our newsletter