Latex ball with mousse tire insert

Gary

Old Tartan Bollocks
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Mar 29, 2018
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the internet
Sorry Gary, regular re-inflating will dry out sealant (slowly, a bit at a time if you keep adding air regularly). The air added will absorb some of the moisture from the sealant. Obviously if you have done a decent job of the install and dont have a slow leak you wont be adding enough air over the year or so to cause it to dry fully, but if you need to top off all the time it will dry out due to adding new air.
Nope.
It's not the adding of air that causes drying but the loss of air.
Have a wee think about why are you adding air, eh?
And have a wee think about air volume in a defined space at a constant pressure.
 

GrahamPaul

E*POWAH Elite World Champion
Nov 6, 2019
1,127
1,087
Andalucía
Wonder what a higher concentration of CO2 than normal air has. I seem to recall reading (I think in the context of using a CO2 inflator to seat a tyre) that it is not recommended in the long term.

0.04% is the concentration of CO2 in air. (And, amusingly, why climate change deniers claim there is no problem because there's obviously room for loads more CO2 without the Earth noticing... I generally suggest they try breathing hydrogen sulphide at the same concentration if such low concentrations are an irrelevance - that would do us all a favour).

Rubber tyres are porous to CO2. It passes through the tyre walls pretty quickly and you will have a noticeable loss of pressure by the morning if you only use the cartridges.
 

Cyclopath1000

Active member
Apr 26, 2019
309
125
Davis Ca
Maybe filling with nitrogen instead of air will prevent this...never thought about it until now...with cars nitrogen is popular as it is less reactive with the steel or aluminum wheel and it doesn't change pressures non linearly when used and the tire heats... You would of course need a tank and a set up. Not worth it to me ...maybe someone out there can try it.
 

urastus

⚡The Whippet⚡
May 4, 2020
1,548
993
Tasmania
It's a doozy. Having an insert displaces a fair bit of air. If anything the sealant should last longer. Unless the insert has minimal impact, and the biggest change is that it is an ebike? EG, something to do with usage or temperatures ridden in? What are the variables here: clockwork vs ebike, smaller tyre vs larger tyre, insert vs no insert. Also, what we don't know, is the OP's usage, has that changed with the ebike?
 

GrahamPaul

E*POWAH Elite World Champion
Nov 6, 2019
1,127
1,087
Andalucía
When I remove the tire I've seen a ball of all latex liquid (Líquido Sellante Tubeless Joe´s 1L) into the tire and no liquid free, and the liquid is not more of 2 month old. I used Eliminator and Butcher tires and Vittoria insert (Air-Liner MTB).

Has anyone else had this issue?

I've been ruminating on this for a while because of a similar problem we have in my industry. When you make concrete you need to add a specific amount of water to the sand/aggregate/cement to arrive at the correct water/cement ratio required to give whatever durability/strength/workability values specified.

Sand and aggregate usually arrive wet. Therefore you need to work out how much water to add to the mix by deducting the moisture content of the sand and aggregate from the amount of water to be added. (Stay with me here, this will start to become clear as to where I'm heading).

To get the moisture content, you stick the sand or aggregate in the oven to dry it out. From the difference in weight between the wet and dry samples, it's dead easy to work out moisture content of the wet material. (Stay with me here...) But if you deduct this full amount from your water to be added you will end up with a dry and unworkable concrete.

The problem comes with not all water being available for use: there is a percentage of the water in sand and aggregate which is there to wet the surfaces. It is little more than a few molecules thick, but is bonded to the surface by atomic attraction. ("Adsorption", if you want to look it up. Rather than "Absorption", which is what happens where a liquid is otherwise free to react). One of the tasks undertaken for concrete mix design is to determine what that value for Saturated Surface Dry Sand actually is. (Very important in desert environments because extra water needs to be added over and above the expect amount from the simple water/cement ratio calculation).

It seems to me that the sealant has a pretty large area within a tyre to wet. That liquid used for "wetting" is not available for keeping latex particles in suspension. Generally you've got enough liquid in a tyre so that this doesn't matter. However, put a tyre insert in there and all of a sudden you've got at least double the area to wet (inside the tyre/wheel + around the outside of the liner). Worse still if the insert is not a sealed, smooth surface, because any pores will also adsorb (not absorb!) liquid.

Put a tyre insert into a tyre and the result is that there is considerably less liquid available to maintain the latex particles in suspension and Stan's Balls will appear much sooner than for the same quantity of sealant in a tyre without an insert.
 

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