So I’m quite new to this whole tubeless thing, had it running 3 weeks or so. Stans Flow rims, Stans rim tape + sealant with ‘tubeless ready’ Nobby Nic snakeskins. No problems setting up etc, but today I was riding along and got a funny puncture on a rocky descent. Right in the middle of the tread pattern, a small approximately round hole no more than 0.5mm. It just wouldn’t seal! Occasionally a bit of sealant would spray out but it didn’t stop the air leak and the tyre went flat. So I did a bit of pumping air in / spinning the wheel / trying to get it to seal and nothing, still leaking air & I ended up having to put a tube in. There was still plenty of sealant sloshing around and it didn’t look manky / coagulated or anything. I don’t understand.

Basically I want to know why this happened, is it going to happen again, and should I try and patch the hole in the tyre before having another go with the sealant?

Its not infallible.I use these tubless plugs and you don’t even have to take the tyre off!!

Did you try stopping and putting the hole to the bottom so the sealant goes to the hole?

I sometimes have success with blocking the hole with my thumb and the hole at the bottom of the wheel. Hold it there for a while and it lets the liquid seal without spraying out.

Yeah I tried holding the puncture down – nothing really came out but then as soon as I spun the wheel more air would come out.

For riding tomorrow would you:

a) stick some more goo in and hope for the best
b) repair the tyre from the inside using a standard inner tube patch
c) just use tubes until you can get some of those repair things.

Superficial –
c) just use tubes until you can get some of those repair things.

This would be my choice. Sounds like you were just unlucky and the whole was just too big to seal.

Its not unusual to get a hole that the latex won’t seal. For these I just glue a standard tube patch to the inside of the tyre.

Only need to remove the 1/4 of tyre where the hole is, and (ensuring you lose no more latex) clean the inside and glue on. Easily done on the trail.

It may need a co2 cannister to reseal, or compressor at home.

Never bother with a tube as there are usually too many thorns etc alresdy sticking through the tyre.

b) Wouldn’t work anyway. You need special a tubeless patch kit which uses glue rather than vulcanising rubber soultion which doesn’t work on tyres.

How much sealant was in the tyre? I have had problems like that when the solution was too old or there was too little left in the tyre. I have had quite some success in just putting some more sealant in and pumping up the tyre again and voila no more loss óf air.

I’ve used a standard repair patch to repair a biggish hole in a tubeless tyre. But normal puncture repair glue (which isn’t really glue) doesn’t work, so I used some of that flexible rubbery superglue you can get from DIY places, the sort of stuff that’s advertised for repairing shoes and the like. That tyre’s still going strong over 500 miles later.

When I holed that tyre I think it was because I was running too low a pressure – you don’t get snakebite punctures with tubeless, but if you wallop too hard into a massive rock you get a whacking great hole instead. Pump the tyres up a bit more, especially on the back if you’re on a hardtail.

i carry a cheap (£1 for 3) tube of superglue for those kind of leaks that won’t seal, tried the strip type repairs, thought they were rubbish. Should be ok with a repair patch on the inside they usual don’t work very well on the side wall but normaly ok behind the tread (IMO due to the flexing).

Could also use this.

Plugging the hole also means that you don’t have to take the tyre off.

+ 1 for tyre plugs, fast easy and more often work really well, even in the wet..

Is there a knack to using these? I tried and couldn’t even get it to go through the needle thingy properly it was so damn sticky (even with the lubricant), let alone get it into the tyre – grrr!

Did you make sure you THOROUGHLY shook the bottle when installing the tyres? It’s possible that you haven’t got a good mix of “yellow crystals” in there.