Great test of different sealants in motorcycle tires

[neptronix]

Really good test here. They roll the tire over progressively bigger nails with each sealant.

I'm not surprised to see that slime came last in protection.

I imagine this translates to similar results in a bicycle tire.

 

[nicobie]

6.17 minutes of misery

 

[marka-ee]

These tests are rather useless and here's the reason:. These substances change their properties after a few days or weeks and the effective nature of what might work when it's brand new changes substantially. I have found this to be the case with slime and also Stans, which is a latex-based sealant. Stans turned to a milky substance that did little to do any puncture fixing.
A electric scooter of mine claims to have some kind of a gel inside of the tire, which so far for me has been working out. I haven't taken the tire off yet, as I haven't needed to, but I believe that if there is a layer of gel in the tubeless tire that has the consistency of a thick jello, not some kind of fluid, then this would be the ultimate solution. Liquids are complete BS in my opinion. It's got to be in a gel format. Gels don't get pushed out of a tire defect and also are obviously completely self-healing. Perfect. Whether anybody makes a gel that could be applied to the inside of a tire I have no idea I'd love to find one. In the spirit of this, I once tried to coat the inside of a tubeless tire with clear silicone sealer, but that didn't work out at all. I think it has to remain in some type of a tacky jelly type consistency to be effective.

 

[amberwolf]

As long as it's a sufficiently viscous thixotropic(?) gel, so it resists motion even when pulled down by gravity, and remains on the outer circumference all the time, regardless of temperature, it should work.

If it is not viscous enough, then over enough time or at a high enough temperature it may pool at the bottom, and if the valve is there it may clog that up, and it will also severely unbalance the wheel until it spins back out to the outer circumference (which might not be able to happen if the temperature drops to make it viscous enough to effectively become a solid...such as say, desert daytime temps in direct sunlight, vs desert nighttime temps, which can easily be 40-50F difference or more.


If you want to experiment, you can get very soft platsil from Smooth-On, and add silicone oil to the mix until it has just the properties you want. It's not cheap, though. There are probably other things you can use, but that's one I have had experience with to make molds for casting scifi prop parts and other stuff in and from.

 

[Chalo]

Liquids are complete BS in my opinion. It's got to be in a gel format. Gels don't get pushed out of a tire defect and also are obviously completely self-healing.

The least awful sealant I have any experience with is Flatout. It's. definitely not a gel-- more of a colloid. I don't think it's intended for high bicycle-like tire pressures, and I don't expect that of it. But it doesn't congeal or precipitate over time, and it does work.

Gels are not inherently self-healing. Try sticking gelatin or agar back together. Try coaxing a ruptured gel padded saddle into an uninterrupted surface again.

 

[neptronix]

These tests are rather useless and here's the reason:. These substances change their properties after a few days or weeks and the effective nature of what might work when it's brand new changes substantially.

But not all sealants are the same.

I second what Chalo said about flatout.. users claim it can last a decade in a tire.. it remains liquid-ish.. one of the few sealants that lasts.
Slime, Orange Seal, Stans are all known to coagulate.

Others? show me the evidence they suck, there's a lot of interesting materials engineering going on and you can't tell me something sucks w/o proof these days

 

[marka-ee]

I got a used bike that had some kind of flat fix material in the tube that seems to work very well. It has very small white threads in it, maybe about 2-3mm long, and they tend to try to get out of the puncture and self-seal it, and quite effectively I must add. I have no idea who made this because I got the tire and tube used, but if anybody has any clues, let me know. The material seems to be white-ish, but the biggest clue are the small threads or fibers, whatever they are. Definitely not platelets or glitter, actual fibers.

 

[kuromaku]

I got a used bike that had some kind of flat fix material in the tube that seems to work very well. It has very small white threads in it, maybe about 2-3mm long, and they tend to try to get out of the puncture and self-seal it, and quite effectively I must add. I have no idea who made this because I got the tire and tube used, but if anybody has any clues, let me know. The material seems to be white-ish, but the biggest clue are the small threads or fibers, whatever they are. Definitely not platelets or glitter, actual fibers.

this sounds like the aforementioned flat-out. afaict, kevlar fibers suspended in a mixture of ground vulcanized rubber bits and propylene or ethylene glycol:

FLATOUT

lower viscosity formulation that i use in typical bicycle-sized tires to help prevent vibration at speed

 

[E-HP]

I second what Chalo said about flatout.. users claim it can last a decade in a tire.. it remains liquid-ish.. one of the few sealants that lasts.

When I had my flat a few months ago, with the 4" deck screw, the flatout looked the same as it did when I put it in a little over 2 years prior.

 

[Chalo]

When I had my flat a few months ago, with the 4" deck screw, the flatout looked the same as it did when I put it in a little over 2 years prior.

What pressure do you typically use? The fact that it isn't recommended for bicycles (only fat tire bikes) is the reason I've limited my use of it to low/lowish pressure tires.

 

[E-HP]

I was running around 30lbs in those knobby tires. It actually sealed the outer puncture, but couldn't deal with the exit wound on the rim side.
I'm at 50lbs with the Hookworms.
When I bought it, they only had the one formulation, but now I think they have three or four. I bought some of the Sportsman's formula this time around, but then realized I still had a half a bottle left of the original stuff, so still using that.