Joe's No Flats Yellow Gel Innertube Sealant

Joe's Yellow Gel Innertube Sealant is effective protection against punctures both in inner tubes and tubular tyres.

No cyclists like punctures, and anything that can help to avoid them has to be good, right? Joe's No-Flats are a company specialising in sealants with a range available to suit most applications. This Yellow Gel sealant is designed to be squirted inside the inner tube where it is claimed to be able to deal with any hole in the tread up to about 3mm in size.

First things first, installing the sealant. That's straightforward but you do need to have an inner tube with a removable core, so you might need to purchase a couple of new inner tubes first. Providing your tubes do have removable cores, you simply remove the core, attach the supplied hose over the open valve, attach the bottle on the other end, and squeeze away.

The 240ml bottle I tested is good for two wheels, with 120ml recommend per inner tube. I decided to be more thrifty and went with about 60ml in each inner tube. Valve core back in, inflate the tyre and give it a few rotations to spread the sealant inside the inner tube, and you're ready to ride.

As luck would have it when testing a product designed to protect against punctures, I got a puncture on the first ride out, thanks to the hedge trimmers. A small thorn had penetrated the front tyre and there was the telltale sign of yellow sealant bubbling out around the embedded thorn. I pulled over to the side of the road, extracted the thorn, leaving a hole about 1mm in size. The sealant bubbled out a bit more. I gave the wheel a few spins, and sure enough the bubbling stopped.

It was clear I had lost a tiny bit of pressure, but I carried on with the ride and another two hours later I returned home. I attached a pressure gauge, turns out I only lost about 8psi. If the inner tubes hadn't been filled with sealant I would no doubt have had to stop and change the inner tube, interrupting the rhythm of my ride, and most likely resulting in dirty hands.

As well as using it in inner tubes, I've also found the sealant ideal for fixing a recent puncture in a tubular tyre that had been freshly glued to the rim a few days before. Since adding the sealant, the tub is still holding pressure, so for anyone regularly riding with tubulars, this sealant is ideal. You can use it to fix a puncture, as I did in this case, but it might be more prudent to use it as a preventative measure, and squirt some in from the outset.

Joe's claim it lasts 12 months, I haven't been using it long enough to verify that claim. As well as the 240ml bottle, it's available in a 5 litre tub if you have a fleet of bikes you want to puncture-proof.

Verdict

Very good puncture preventative for the cost of a couple of tubes