Bat Tyre Sealant

Bat Tyre Sealant is a latex-based sealant infused with suspended particles designed to clog holes quickly, and it's something it does well. It seems good at staying liquid instead of drying out, but this small bottle works out pricey and it's generally tricky to track down.

Bat claims this uses 'rapid seal technology' so punctures seal faster while using less sealant, but is more or less silent on what that 'technology' actually entails.

Any details as to who or what Batseal is or does are incredibly hard to track down, but the South African company does use very funky cartoon-inspired graphics (Lichtenstein, if you're feeling cultured) that stand out when you do find it.

Glug

At a guess, 'rapid seal technology' is strongly linked with 'having bits in.' Rub a bit of shaken-up Bat Sealant between your fingers and you can feel the gritty friction of these particles, and leave a small bit in a saucer it will separate slightly and the particles will become visible. It's definitely worth following the instructions and shaking it all up before glugging it into a tyre, so they can swoosh around and be ready for hole-clogging everywhere.

Despite the big particles it's still an easy liquid to squirt through a valve core without instantly gumming it up. Bat recommends 60ml per tyre for racing snakes or 125ml for more regular use, which means this 125ml bottle is good for one tyre if you're pragmatic or two if you're feeling brave.

Bat doesn't say what size wheel and tyre these measurements are for, though these volumes suggest a mountain bike so you might make it last a little more.

Spray

I didn't get any hiss, bubble, spurt or spray indications that the sealant was having to work hard, and the existence of some thorns embedded in the tyre (a cyclist's nemesis around here) indicated that it did its job perfectly.

In lieu of any real world tyre slashes or gashes to test it I had to resort to the heartbreaking task of stabbing a tyre with various implements to see how Bat Sealant would cope. I started easy and poked a stout safety pin into the tyre and that didn't raise any issues at all.

Spurt

Next up was a small Phillips screwdriver, which again led to no loss off air. I upped the stakes with a bradawl and, after some initial spurting it firmly sealed, which was pretty good going.

Then I got serious with a 3mm metal shaft, which refused to seal with the wheel spinning; only by rotating the hole to the bottom and jiggling things about to help did the hole eventually seal. That would be one to fix with a tyre patch or with a tubeless plug.

Slash

Finally it was time for the killer blow – a sidewall slash performed with the Brutus stab of a 10A scalpel. This type of slit is a big ask for any tubeless goo but sometimes, just sometimes there's a partial clogging, but this wasn't to be with the Bat sealant.

> Buyer's guide to tubeless tyres – find out all about new technology rubber

An issue with some latex based sealants is that over time the liquid can evaporate, leaving a solid lump of rubbery sealant that's unable to do its job and can be felt as a wheel imbalance.

I'm happy to say that, despite the test bike being left standing for various periods, the sealant didn't transmogrify over time into the dreaded tubeless cuttlefish, and remained sloshing around the tyre when the wheel was finally rotated back into life.

Value

At £6.99 for 125ml this is at the more expensive end of things, especially as there are always discounts to be had for the more popular brands. Stu reviewed and liked the CST Tubeless Tyre Sealant at (these days) £10.30 for 250ml, although it struggled to match its larger-hole sealing claims.

An obvious 'latex liquid with bits in' competitor is Stans NoTubes Race Sealant, which comes in a 946ml bottle for £40, or £5 per 125ml (though it's easily for around £30). It gets cloggy fast enough you can't even get it through a valve core, but that does mean it does its hole-plugging job well. Obviously buying in bulk will always work out cheaper, though, so Bat is not quite as expensive as it seems – and there's a 400ml bottle that would surely be better value.

Overall

The tubeless fluid market is quite the minefield: one person's favourite goop has led to another's absolute nightmare moment, and I've been victim myself, watching a trusted suggestion merrily jizz all over my ankles and bike frame. Real-world use of the Bat Sealant suggests it performs rather well though, and the presence of sharps and thorns still wedged in the tyres shows it did exactly what it was supposed to.

Verdict

Does a good job of sealing holes, but it's not cheap – or easy to find