Tubeless & CO2

slowhand44

I am changing my setup to tubeless, and as I haven't got one of those pumps that give a big boost of air to seat the tire, I was going to use CO2. However, I have been given conflicting advice as to whether this is a good idea. One bike shop said i shouldn't do it, as the CO2 will freeze the sealant in the tire, whereas someone else has told me they use CO2 regularly with no issues. Which is correct?

lostboysaint

The latter.

shmooster

I use CO2 to get the tyre mostly seated, then my standard track pump to 100psi to make sure the bead is properly seated (there's a loud pop if it wasn't). I then deflate, install sealant and then reinflate with the track pump. Worked fine with Schwalbes. You wouldn't be doing your initial seating including sealant unless you are looking for a reason to buy a new carpet.

EDIT, sorry, thats road tubeless, MTB may be different, wandered into the wrong forum ;-)

larkim

Is there sufficient volume in a CO2 capsule to reliably get a tubeless tyre up? With the (occasionally) hit and miss approach to getting a tubeless tyre up first time, the possibility of wasting a few CO2 capsules seems moderately high at the very least?

lostboysaint

Yes there is.

They're a few pence each. Hardly something to be too worried about.

larkim

Fair enough, I've got a CO2 set coming at christmas so will be intrigued to try it out.

They're still around 50p each aren't they? Last time I inflated some tyres I had at least 3 failed attempts - I'd rather that was free than £1.50 each time! Though I can see the convenience when being used out and about.

lostboysaint

Depends where you buy them but usually around 50p each.

You probably spend more than £1.50 in the time wasted trying to do it with ghetto inflators or track pumps. The best alternative I have is to get a track pump such as the Bontrager Flash Charger which can store compressed air and then blow them up on the release of a lever. But it costs a LOT of cartridges!

larkim

I've got a fire extinguisher ghetto pump already built so no need for me to use CO2 for tubeless inflation at home - probably cost about £10 in total, so not bad VFM and fun to make.

The Rookie

Coke bottle accumulator for me, cost about 50p.....

JBA

Pop bottle ghetto inflator for me as well.
A 2-litre bottle, 2 valves, a length of rubber tubing and about 30 minutes is all it takes.

larkim

I did have a coke bottle one, but it got a bit battered and bashed mainly due to my carelessness so I went for something a little bit more robust that I could trust with the pressure! Plus the coke bottle setup that I used had a rubbish bit of tube on it so it was a bit challenging to use - nothing I couldn't have fixed if I'd been bothered, but the fire ext approach looked fun!

trivial_poursuivant

Lighter fluid and a match :-)

Works on car tyres

02gf74

slowhand44 wrote:

One bike shop said i shouldn't do it, as the CO2 will freeze the sealant in the tire, whereas someone else has told me they use CO2 regularly with no issues. Which is correct?

The co2 or any other gas that has just rapidly expanded may freeze the sealant but it won't be permanent.

cooldad

Mine seat and go up easily with a track pump, but I have Bontrager rims, rim strips, tyres and sealant.

cycleclinic

If you infalte the tyre with c02 dry to get it seated then all will be well. Then add sealant. If you use Co2 on a tyre with sealant in place latex creatures form the liquid either turn watery or disappears (no idea where) and you have to add more sealant. C02 is very useful. On the trail it can cause a puncture that does not want to seal to seal. Then add more sealant through the valve stem and inflate with a pump.

02gf74

thecycleclinic wrote:

. C02 is very useful. On the trail it can cause a puncture that does not want to seal to seal. Then add more sealant through the valve stem and inflate with a pump.

This is interesting. In my earlier post I was going to say that co2 in the tyre is better as it will help prevent the sealant from drying up, I'm assuming that the sealant reacts with o2 in the air.

So maybe having no o2 in the tyre is bad?

cycleclinic

It's not a chemical reaction. It is to do with the large volume and temperature of the gas. It could be any gas. If you have stans in your tyre and you use Co2 rubber creatures appear thus mean the fluid left behind is watery and has less latex and is therefore less effective. Adding more sealant helps but it is still is a more dilute solution.

Effetto mariposa just disappears with Co2. Zeal sealant does a similar thing as well. Well it turn to rubber but where does the fluid go. No idea what happens to orange seal with c02.

I have tried this all out with road tubeless tyres. But even with higher volumes of sealant in mtb tyres the results are not good.

larkim

Was trying to work out Boyles law etc for CO2 cartridges.

With a 16g cartridge of CO2 and a MTB wheel volume of 5.5l (estimated) at 20degC, the pressure from a whole cartridge would be about 23psi if my googling and maths are correct. Enough to get it up (!) but not much room for leakage / losses. Irrespective of whether it does odd things with the sealant.

ryan_w-2

The Co2 should be no where near the sealant.

You should never inflate a tubeless tyre with the valve at the bottom.

Have the valve at the top, sealant will be at the bottom on the tyre. No issues.

larkim

I'm intrigued by your ability to control where the CO2 is present in the tubeless tyre Ryan?

I presume what you really mean is that you shouldn't have the very cold CO2 when it is released directly contacting the pool of sealant and freezing it. But, and this might sound very patronising, once the CO2 is in the tyre, its in the tyre and will be the main gas in contact with the sealant surely????!?

trivial_poursuivant

Ryan_W wrote:

The Co2 should be no where near the sealant.

You should never inflate a tubeless tyre with the valve at the bottom.

Have the valve at the top, sealant will be at the bottom on the tyre. No issues.

But the flat bit is always at the bottom. Its never at the top

larkim

Depends if you’ve got the wheel on the floor or suspended in the air, as preferred.

trivial_poursuivant

larkim wrote:

Depends if you’ve got the wheel on the floor or suspended in the air, as preferred.

I’ve not mastered levitation yet.

larkim

I hang the wheel up when I'm inflating it. Or if I was out it would probably be bike on its back.

JGTR

Hope I don’t get a puncture.....sounds complicated, you lot seem to really struggle with it

02gf74

Yes, it is a struggle, I resort to using a air compressor.

And carry an inner tube should one tyre goes down on a ride.

Steve-XcT

Out of a fair old set of rims and tyres I only have a couple need anything except a track pump.
(My 8yr old can seat his Stans Crest and Rocket Ron's with a smaller track pump.... just with taking the valve core out... )

I would try first before wasting CO2 cartridges.
I have a 15p "lemonade" (Morrisons cheapest) pop bottle wrapped in 50p's worth of tape and some old valves and some tube I had left that fits shimano callipers for bleeding (I got a meter for <£1) and this seats the couple of stubborn rim/tyre combinations I've got. I've also got some on a syringe and a thinner pipe inside (part of a inner sleeve from gear cables) that pops inside the valve with the core removed and makes it easier to get sealant in.

cycleclinic

I have inflated tyres with co2 and sealant present and the valve at the top and the sealant is non existant afterwards

cycleclinic

I have inflated tyres with co2 and sealant present and the valve at the top and the sealant is non existant afterwards. Thats on road tyres. With MTB tyres you have more selant and you might get away with it but if you are using stans then some latex will fall out of solution and form rubber creatures and leave the remaining liquid less able to seal holes so please no one say valve at the top and no problem that is simply not the case.

swod1

cooldad wrote:

Mine seat and go up easily with a track pump, but I have Bontrager rims, rim strips, tyres and sealant.

Mine are similar but using mavic ust tubeless ready with maxxis tubeless tyres go on with a track pump just take valve core out to force more air in.

Stans I've heard doesn't like using co2 on it but I hear uberbike tyre matrix is fine to use with co2.

I'm trying tyre matrix next once I've used up the stans I have left, a bit stupid to by a litre bottle, was cheap at the time.

slowhand44

Thanks for all the advice and opinions. I have ended up buying an Airshot to complement my track pump.