Yet more sealant, Vicar!

[Tootyred]

Something I've always wondered about is the issue of sealant movement in the tyre.

We seem to worry about a tube adding 50g of rotational mass to to wheel, but that is even mass as the tube stays still.

 

[2manyoranges]

Something I've always wondered about is the issue of sealant movement in the tyre.

We seem to worry about a tube adding 50g of rotational mass to to wheel, but that is even mass as the tube stays still.

Centrifugal force…..

Forces sealant into a layer of coverage over the tyre casing, as Centripetal force sends the sealant outwards. So in reality it becomes static and contributes to rotating mass. The different brands do behave differently, though. Stans = gloopy. MucOff = a mystery. Effetto Mariposa = deliberately foamy.

 

[Tootyred]

Yer...i get the centrifugal force bit, but the only bike i ever had with sealant in, when the tyre wore out i took it off to find it was quite "clumpy" and had gone gooooey....messy!

As the option was 100g of tube of 100g of sealant..tbh....i put a tube back in it and carried on with the new tyres.

Im just interested, does it always clump with age...say round the valve? Kinda forming a mass in the end?

 

[Tootyred]

Also, is it ok to use in low mileage bikes? If they stand for maybe months over the winter? Or is it just a case of rotating the wheels once a week?

 

[2manyoranges]

Also, is it ok to use in low mileage bikes? If they stand for maybe months over the winter? Or is it just a case of rotating the wheels once a week?

Interestingly it varies from bike to bike - I worried about using tubeless on bikes which are not in constant use and really fretted about it before I appreciated the benefit of low pressure running and the puncture sealing. I stored some DH bikes elsewhere and could not do the rotating thing. Then I opened up a DH bike which has been left in the Alps for 9 months (yes 9 months) and it was full of viable sealant (Stan’s regular) - tape = muc off, tyres = Magic Mary F Supersoft and Hans Dampf soft R. Which was good. Two hardtails not used for 6 months (Stan’s regular) - Schwalbe TLE - same good experience.

But I think there are very different interactions between tape and sealant and tyre. Some combinations do seem to result in what are called ‘SNOTITES‘ or great lumpiness. It seems that the plasticisers in tyres can initiate reactions which create solids. and the fibres in different fluids do seem to behave differently as sealant ages. Quite a few stories of this but certainly not my experience. I have started to use Mariposa Effetto Cafe Latte (seems to seal better on reluctant tyres like Pararacer GravelKings) and am anxious to see how it behaves over time.

So far I have used:

Sealant
Stan's regular
Mariposa Effetto Cafe Latte
MucOff race sealant

Tape
Stan's
Tesa (same as Stan's..they are the OEM manufacturer in CH)
Muc-Off

Tyres
Schwalbe
Specialized (horrible leakage through tyre wall ... a sort of sad weeping)
WTB
Panaracer
Maxxis

Rotating the wheels once a week, listening for sloshing (a good sign), and topping up every 4-6 months (60ml) is certainly good practice.

 

[clubby]

Also, is it ok to use in low mileage bikes? If they stand for maybe months over the winter? Or is it just a case of rotating the wheels once a week?

I also find it varies between tyres. Beefier casings tend to be fine. Not surprising as there is more rubber in the sidewalls. XC tyres tend to weep a lot more and need more frequent topping up. Worst offenders in my fleet are the Scwalbe Racing Ray/Ralph combo. Magic Mary hardly ever needs any. Same story with losing pressure while sat.

As far as I can tell, clumpy bits are a more random phenomenon. The fibres suspended in the sealant need a seed to start accumulating around. This could be a bit of dirt that gets inside the tyre when fitting or a lump of sealant that has fallen away from where it has sealed a leak. Once this starts it's a snowball effect. Adding more sealant doesn't help and the only way to stop it to clean out inside of tyre and start with fresh sealant. That said I've had a couple of big ones and never felt them while riding.