What tubeless sealant?

[Gattopardo]

On motorbike tyres I've used slime, when I have had a puncture.  Worked and no problems after with washing it out.

[bludger]

I've had good results from trimming the plugs down with scissors and widening the hole a tad with the bradawl supplied in the velox tubeless plug kit.

[Carlosfandango]

I'm currently using the Orange endurance, BUT that is for 50psi or less.  I'm not sure it would be ideal for higher pressures (where I'm still using tubes, on the grounds that I'm not sure the technology is quite there yet).

most sealants will seal punctures from pins/tacks/wires just fine, even at high pressures. the problem is cuts from flints and glass, which are typically 2mm+. it will eventually seal after the pressure drops down to ~30psi, which is still rideable and a better scenario than stopping and faffing about on a muddy verge.
ideally the sealant should plug cuts up to 4mm, leaving tyre plugs for anything bigger. currently it's a tricky situation with ~2-4mm cuts - they are too big to seal and too small to push the tyre plug through.

If your sealant isn't sealing until 30psi, it isn't much good.
You'd be struggling on 28mm tyres at 30psi, 25mm, no chance.

Even on 2mm cuts it should seal, above that you can easily push in a worm.

I recently had a 3mm cut which I didn't notice until the next morning when the tyre was soft. So only a partial seal, but I got home without noticing. I pushed in a worm, topped up with sealant and it's been fine for the last few hundred Kms.

[morbihan]

Panaracer have a new sealant on the market that Rene Herse recommend for their tires. Its expensive though.
https://www.renehersecycles.com/shop/components/tires/700c/panaracer-seal-smart-tire-sealant/

[zigzag]

If your sealant isn't sealing until 30psi, it isn't much good.
You'd be struggling on 28mm tyres at 30psi, 25mm, no chance.

Even on 2mm cuts it should seal, above that you can easily push in a worm.

I recently had a 3mm cut which I didn't notice until the next morning when the tyre was soft. So only a partial seal, but I got home without noticing. I pushed in a worm, topped up with sealant and it's been fine for the last few hundred Kms.

firstly, 20psi in 25mm tyre is still rideable pressure, i've done it on two occasions until the tyre could be sorted. (this may not apply to heavier riders)

punctures or cuts up to 2mm seal fine with little pressure loss with most (but the worst) sealants, larger cuts cause substantial pressure loss. i've yet to see a proper* test for sealant efficiency in high pressure tyres.

* e.g., a selection of 1, 2, 3, 4, 5mm blades (in shape of miniature swords); 10 tyres containing 10 best sealants and inflated to 90psi. how much air/psi would each tyre lose when punctured with different blades before it seals?

[Carlosfandango]

At 20 psi none of my tubeless tyres will stay sealed on the rim!

[zigzag]

At 20 psi none of my tubeless tyres will stay sealed on the rim!

they should stay seated and sealed at 0psi, perhaps the rim is not tubeless compatible or not made to spec.
i rode a considerable distance on 20psi before i noticed that something is not quite right (as can be seen from wear on the sidewall):

[Carlosfandango]

The tyres will stay locked on at that pressure, but not if I try riding the bike.

[tincaman]

I've used Orange Seal in the past which worked very well, but it does leave dried sealant on the inside of the tyre. Switched to Magic Milk Hi-Fibre which doesn't contain latex at only £8 per litre. No problems with that either and it doesn't dry out either, just seems to evaporate.

[Arno]

I started with Orange Seal endurance, used on both a bike with 35mm hutchinson overrides at 3 bars  and on a road bike with 25mm Fusion 5 performance inflated at about 5 bars.
Used on the commute to work, have had 4 or 5 punctures, mostly small glass cuts of 1 to 3 mm and flint in one case, all of them in wet weather.
My experience of this sealant was not a good one. Pressure going down to 20 psi and very slow to seal. Needing to re-inflate once or twice to arrive underinflated at home.
I've recently switched to Cafe Latex, and had 2 glass punctures with it one on each tyre type , both sealed quite quickly and resulting in about 1 bar of pressure loss in each case.
So am now sticking with that sealant.