So, when i’m swapping over tyres on my many and varied sets of tubeless wheels, I am constantly finding only large lumps of dried spongy rubbery tyre sealant. It’s happening after even a weeks use. Not a problem, as the tyres are staying up, but what until i get a significant puncture? there wont be enough left to fill the hole!

I’m using Stans sealant, and i’m putting air in ’em. What’s up?

Are you using CO2 to inflate?

Where do you store your bike? Somewhere warm?

yes! CO2…. is that what the problem is?

Bike is in bed next to me every night.

CO2…. is that what the problem is?

Most likely

I’d go with the CO2 being the problem then (never used it myself though). If you store it, e.g. next to the boiler in the garage or leaning against a radiator or similar that could be what’s drying out your Stans too. Although it sounds like you’re topping up the jizz regularly… 😉

I get them too but I never use CO2. I think all the rubbery little bits conglomerate, seems to be worse with new tyres, had one in a new Geax tyre that was so big it wouldn’t roll inside the tyre.

curious…. howzat then?

I don’t have a compressor (nor the space for one) and my tyres never go up with a track pump. I just buy CO2 carts, from an online place cheap as chips.

Stanimals…

It’s happening after only a week with the last wet. I put on some DH tyres for my Alps trip, upon returning 10 day later………. this

Apparently CO2 reacts with the latex to form big lumps of stuff. Searches on tinterweb will probably find the actual chemical reaction.

There are two ways to avoid it (that I know of).

1. Use CO2 to inflate the tyre before putting the white gloop in. Then, once the tyre is seated, deflate, add the gloop through the valve, and reinflate with a track pump.

2. Use a ghetto inflator to mount the tyre initially. This uses ordinary air and is also a lot cheaper than CO2.

@rickmeister….

Stanimals????

@oldnpastit…

Thanks for the info. Thats a bugger, as its the only faff-free way i’ve found to get those tyres up. Maybe i’ll let the tyres seal with the sealant in, and use the CO2. Then, remove the balls of spongy stuff, and re-fresh the sealant.

it’s a faff tho’

Thanks anyway.

@lardman – do it the other way round.

Get the tyre up without any Stan’s to start with. The CO2 will pop the tyre bead onto the rim and it will then stay up. It might need a bit more easy pumping from a track pump, and it will probably slowly deflate. That’s fine.

Now, let the CO2 out, unscrew the removable valve hole, and inject wheel milk through the valve core with a syringe.

Then reinflate with your trusty track pump.

Or use a ghetto inflator which costs next to nothing to make and is a lot easier and cheaper than CO2.

EDIT: the other way to do it is with a syringe that has an actual needle. Just inject straight through the tyre wall. I’ve never actually tried this myself though, YMMV….

ok, cheers. i’ll try it that way round next time.

Happens when I’ve use Stans, no CO2 involved. It’s just how it separates in use.

Stans seems to have gone downhill imo. I’ve been getting massive (fatbike sized :-)) stanimals recently which I never used to. They appear quickly too.
Never ever used CO2.

No such issues with Fenwicks or Slime Pro stays liquid for 12 months

Always use compressed air from an air compressor to do mine. Had a strange rattle like a marble rumbling and found a lump in the rear tyre of rubber sealant. Hasn’t happened since and was only on one wheel, even though I put front and rear tyres on together. Weird……..

Stans seems to have gone downhill imo. I’ve been getting massive (fatbike sized :-)) stanimals recently which I never used to. They appear quickly too.
Never ever used CO2.

Are you tyres old and getting more porous?

Stans shouldn’t be used with CO2 because of the low temp. Slime has antifreeze and is OK with CO2 or so I’ve been assured.

Stanimals…

Round here they’re known as Sealant Bunnies

Stans contains something like proplyne glycol, basically antifreeze. The cold or co2 isn’t anything to do with bogey formation. Its some ingredient that causes it as the alternative to the latex content drying and hardening as a thin layer on the inside of the tyre, as homebrew stuff using mold latex does.

I use co2 for tyres that have burped etc. no problems

Used the emergency compressor and sealant kit on my car a month back. Grey foamy lumps everywhere when we took it off.

I’m not convinced its co2

It’s been long reported that CO2 does react with the stuff, but I’ve just avoided mixing it just in case. I do still get the lumps but only after long use and the sealant has dried up. Oddly I’m finding I need to refresh sealant more often recently, especially on my bigger tyres. They’re 2.4/2.5 EXO Maxxis stuff.

Anyway, as above I still use CO2 to seat the tyres though. Likewise I can never get them to seat with a track pump and CO2 is cheap and easy. Just seat, deflate, pop bead and pop in sealant, then pump with track pump. Got the knack of it now so it’s not much hassle. I have removable core valves on one wheel set so can avoid popping bead but I find the sealant quickly blocks up the valve and I make more of a mess with it.

No CO2 (well, just the normal amount that’s floating around) and I got this:

Does anyone have any evidence at all to explain how CO2 does this, or is it pure anecdote? CO2 is chemically inert so I can’t see it causing this. Alternatively, perhaps there’s something in the air that acts to actively prevent lumps. Both seem equally unlikely to me.

At any rate, my experience is that I get these lumps and I’ve never used CO2.

The whole use CO2 to inflate, then empty it out, then reinflate with air seems like a huge waste of time to me.

I just use a track pump to inflate the tyres, never needed anything else. It just requires a lot of pumping and a small amount of swearing at it. I wish I was man enough to inflate them with a hand pump but I’m not there yet, more training is required.

Yep, there’s absolutely no way my ‘Ghetto’ tubeless will inflate with a track pump. Doesn’t matter how hard i pump. My ‘proper’ UST wheels/tyres do go up with a track pump but only sometimes. Co2 is the only way I have found that works, but comes with uninvited guest ‘stanimals’.

The “stanimals’ you see in the image above came about after 12 days in a brand new set of Maxxis DHR UST (3c compound) tyres, and when i removed the tyres there was NO sealant left at all, just one ball of rubbery bit per tyre and a little clear fluid.

I’ll try some different sealant maybe to see what happens.

Stans reacting with the release agent that coats the inside of the tyres?

I had one rumbling round in the rear of my Cotic. It’s never seen CO2. None of the other tubeless tyres I have have done this, but it did have a 1cm cut in the tread area of the tyre which had healed after a big rocky ride, at the end of which a lot of air had escaped, but the cut had sealed. My theory is that the clotting had taken place over the several seconds or even minutes that the fluid rushed to seal the cut, creating the Stanimal which broke free eventually and then accumulated the granules in a big bogey.