Home

Rookie question: I've got one of the kits that has a CO2 cylinder in it for pumping up a tyre, but no indication of how will be used.  Any guidance for a 700x28 tyre?

6 comments

Avatar
samcannadine [57 posts] 11 months ago
1 like

Cartridges come in different sizes – 12g, 16g or 25g.  The smaller ones are designed for filling tires up to about 90 PSI.  The larger ones are designed for filling tires up to 120+ PSI.  This corresponds to lower pressure tubes such as clinchers (typically 90-120PSI) and tubular’s (140-170 PSI) such as race wheels.

credit to DC rainmaker, full content here : https://www.dcrainmaker.com/2008/08/how-to-use-co2-for-cycling-beginners...

 

Avatar
StraelGuy [1442 posts] 11 months ago
1 like

Because they freeze when used, you rarely get all the gas  out of one. In my personal experience, a threaded 16 gr cartridge will fill a 25 mm tyre to 'useable' pressure with a bit of CO2 left over when you get home which you have to dump to take the cartridge off.

Avatar
dmack [35 posts] 11 months ago
0 likes

Thanks guys

Avatar
Canyon48 [990 posts] 11 months ago
2 likes

I find a 16g cartridge easily takes my 25mm tyres to 100 psi with plenty left over.

Avatar
Swami Dave [58 posts] 11 months ago
3 likes

Yep, a 16gr will do my 25mm tyres to around 95 psi with a wee bit left over so a full 16gr should do your 28s. I find the pressure drops pretty rapidly with CO2 (down to 50% within a day) so as soon as I'm home I empty the tube and just pump it up normally.

Avatar
StraelGuy [1442 posts] 11 months ago
2 likes

Good point Dave. CO2 diffuses through rubber quite quickly so always remember to let all the CO2 out when you get home and pump up with air.