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Stans sealant with CO2 does not mix?
NB: Originally posted elsewhere on the Global Riders Network and appears via syndication.
Can't recall where I read it but I'm sure it was here on Nobmob. Someone was saying that its not a good idea to mix Stans sealant with the gas ....
or was it just to inflate a TL ready tyre with CO2. cant recall exactly.
I know CO2 deflates after a while its only really there to get you home or back to transition in a race & then re inflate the tyre with proper air.
but why exactly was it not a god Idea to use CO2 with the Stans's sealant?
I use sealant in my tyres I also use CO2 when I've had a burp or a flat to re-inflate my tyre.
So whats the deal? 
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Latex polymer is stabilized in an aqueous solution (soap) that bonds the latex particles with water. Without the solution latex would be a white powder. The pH of this solution is typically between 9.0-11.0
The addition of gaseous C02 into the solution lowers the pH to around 6.0. This destabilizes the aqueous solution which causes the latex to shear coagulate. (copied from mtbr)
CO2 is acidic, so thats all I can think that would cause problems. Possibly reacting with the sealant and hardening it?
The combination of UST wheels and tyres I use have never had any sealant and have never leaked or burped air out. Other brands Ive used are faired far worse, burping air out all the time.
My understanding is that the CO2 reacts with Stans latex and clumps or binds it together, you can see this in the hard 'crystalised' clumps. So the Stan's liquid is reduced and stops sealing. Use CO2 to complete ride, remove tyre and clean rim and inside tyre, replace and use new Stans. I believe some sealants don't interact with CO2 though.
FWIW.
^^^
Are you serious? You have to clean everything out and start again. What a frikkin PAIN IN THE ARSE!
I know if you don't have UST rims you don't have much choice, but what a hassle.
The worst ive had with XT rims and Maxxis tyres and NO sealant in 10 months is the front needs a quick pump every week or two.
I couldn't deal with the mess of sealants.
Yeah - I cant imagine that the sealant would be ruined in hours - maybe if you left it in there a few weeks - if i use co2 I will let the air out when home, and re pump with air next time though. have never experienced in real life stans crystalizing due to co2 - though have experienced stuffed sealant after 5 months in the tyre.
Don't assume that the CO2 does react with the Stans, has that been confirmed. I've seen the latex monsters form in tyres that have never had gas and likewise has the goop work fine for up to a year after using gas
I've always pumped up my tyres with a proper pump, but use Co2 on the trails.
For some reason, I always use the co2 with the valve up high so the sealant runs down away from a direct blast of co2.
I have no idea if this makes an actual difference, but the 2 times I've done this, I found no monsters later.
Edit: I recall the Stans website saying something about not using co2 unless you had to?
I recall reading in a magazine that the CO2 freezes the latex...
No idea if it's true but I'd love to know a definitive answer
CB
Ok - just to clarify - no YOU don't HAVE to remove and clean everything if you don't want to. You can let the air (CO2) out and re-inflate after the ride has finished. But on Stans web site they state dont use CO2 and in one reply to a user they state "Your problem is probably from using Co2. Co2 can cause the crystals to clump together. Suggest you open tire. Check for large clumps of sealant. Add fresh sealant and try to reseal." (Incidentally this wasn't the riders problem but the point remains!)
and from another post by Stan's
"It (Co2) can shorten the life of the sealant in that it can turn the once liquid sealant into one rubber ball. If you must use CO2, you can inflate the tire without sealant, then deflate the tire and add your sealant through the valve stem. With most tire and rim combinations, the beads of the tire will stay on the benches of the rim making re-inflation much easier."
If you need to use C02 to get home use it, fill with the valve at the top. Just let Co2 out and re-inflate - but it may be advisable to check the amount of Stan's in the tyre. If you leave the C02 in for some time I'd follow Stan's advice above and clean away any rubber that is on the tyre bead or rim.
Also as the temperature now is rising I'd follow the recommendations of Stan's in refilling with the sealant.
Some other sealants don't suffer the Co2 problem as they use different ingredients.
FWIW.
TOO
FUCKING
HARD
all good. Its a walk in the park. Thank you for everyones input.
I'lll still use the CO2 if I have to. just re infl;ate the tyre with air as soon as I can.
I had one of those crystal thingies in my tyre I changed last weekend. i thought it was unusual. I don't recall when I used the CO2 on the rear last but it wasnt leaking a lot of air.
That crystal thingy was probably due to Co2 being in the air, about 375 parts per million. Thats why you need to check the state/amount in the tyre every so often. Dang may have to join in the reduce Co2 movement, all that Co2 being pumped into the air is messing with my Stan's sealant!!!
I put new tyres on my bike just before the cape to cape (they didn't get used in it, but that's another story). I had a fair bit of trouble trying to get the tyres to seat, so CO2 was used to give it the kick it needed, then it was inflated with a track pump to 40 psi.
So far, I've had no issues except for the slight pressure loss over a few weeks that is normally experienced with new tyres.
When these tyres come off, I'll have a look at the sealant and see if there's any difference to the previous set.
Tyres: Schwalbe Racing Ralph
Rims: Bontrager Race Light 29