I had to use my CO2 inflator the other day for the first time - 23mm road tyre to ~110psi. How much of the 16g cartridge will that have used?
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How many tyres will a 16g CO2 cannister do?
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Posted 2 years ago #
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more than half. does you pump not leak the rest of the air out when you remove it from the valve?
Posted 2 years ago # -
All of it. Or as near as can be measured. Whats left in the cannister will be bugger all and probably won't be worth faffing about with. Just use a new one each time. My 32mm cross tyres make about 80psi on 1 cannister.
Posted 2 years ago # -
It's something like 130/140psi from one 16oz on a 23 road tyre, and 40psi on 2.1 MTB tyre (from memory and a CO2 supplier's website)
Posted 2 years ago # -
the density of carbon dioxide is around 1.98 kg/m³,
so 16g is 8 litres. Now you just need to know the tyre volume... if it were 2L then you'd get 4 bar or 1L would give 8 bar (120psi) The initial pressure will be slightly lower as the gas comes out cold
Posted 2 years ago # -
more than half. does you pump not leak the rest of the air out when you remove it from the valve?
Nope, Specialized Air Tool - has a push valve.
Thanks for the info all - sounds like a new cartridge is required.
simon - good maths - now all I need to work out the volume of a torus, with a odd shaped cross section!
Volume of torus = volume of cylinder = (cross-section area)(length)
Can't be bothered to try working that out!
Posted 2 years ago # -
π * (r squared) * circumference
circumference = 700mm * π
which gives 700mL for a 2cm diameter tube or 1L for 3cm. I don't know how big your tyres arePosted 2 years ago # -
So that (π(r^2)).(2πR) where r is the radius of the tyre (11.5mm - see my first post), and R is the radius from centre of wheel to centre of tyre. All assuming the tyre is a circle cross section.
(3.141592654*(11.5^2))*(2*3.141592654*315)
(415.5)*(1979.2)
(822357)mm^3
(822cm^3/ml8 bar*822ml=6.576l used = 82% used.
Yes. I'm bored. And it's still empty
Posted 2 years ago #
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