Words: #CountryCyclist Ian Macleod
Mountain bikers love their kit…
We (yep, I’m pretty confident I’m in this fraternity now) put plenty of thought and money into our bikes especially. They’re also more complex than road bikes, and have far more than can go wrong. Every so often a new technology emerges that eliminates a huge category of problems, and this spreads through the MTB community faster than Greg Minnaar on home soil (roadies might not get that). The current talk of the trail is the ‘tubeless conversion tyre’.
You’ll recall mending flat bike tyres as a kid. First you pull the tube out of the tyre, then pump it full of air and pull it through water to see where the bubbles are emerging from. Mark the spot with chalk, stick a patch over the offending hole and you’re nearly ready to roll again. But that’s a hassle. On a multi-stage MTB tour, it gets old very quickly.
Enter the tubeless tyre. The concept is not a new one; your car has tubeless tyres. It’s just been adapted and refined for use on mountain bikes. Americans aren’t big on this, so we do the conversion to bikes when they arrive here. Once that’s done, the vast majority of punctures will be automatically healed by the magical goo that sits inside the tyre. Think of it as a rapid-response pit crew, always on high alert to silently save you 15 minutes of tinkering in the dirt on the side of the track.
#CountryCyclist guru Andrew McLean explains:
“You’ve got to have a tubeless conversion. In the harsh African climate, with our thorns and our rocks, you can’t ride tubes.
The tubeless conversion is a really simple process. We seal up the holes where the spokes come through the rim, put a tubeless tyre on (much like on your car) and put some sealant inside before pumping up the tyre. Then almost all the thorns and so on that puncture the tyre will be hardly noticeable for you, other than maybe a few spots of white on the back of your shirt when you finish. That sealant is amazingly quick at getting into the punctures and solidifying.
You will hear some guys worrying about the weight. Now some guys reckon they don’t want to ride with sealant because it means extra mass. But it’s a matter of a few grams. I actually put in more of the sealant than is recommended. I don’t mind having that tiny bit of extra weight if it means I stop far less. You should ask guys who are sitting repairing punctured tubes if they don’t feel the same.
That said, every now and then you might cut a side wall really badly. The main cause is hitting a sharp rock at an angle. In that case you’ve got a spare tube and you put it in just to get your bike going until you can sort the tyre out. But that’s a fairly rare occurrence.”
McLean does offer some caveats:
1. You won’t be able to re-inflate just with a pump. You’ll need a ‘bomb’ or some other high-speed method.
2. If you do use a bomb, it can damage the sealant. Be sure to top up on that when next you can.
3. If you’re going off to ride off-road somewhere like Europe, you can happily use tubes. Just evaluate the terrain.
4. When you ride tubeless, carry a spare tube with your tools. You’ll only need it very rarely, when the tyre is too badly damaged even to repair with a plug, but it’ll mean you can get to the end of the stage.
From my side, Cycle Lab has done the tubeless conversion on my Scott Spark 910. Over the last few months I’ve done plenty of riding on a variety of surfaces. Total punctures sit at zero. Andrew does, however, recommend dedicating a Saturday morning to practising dealing with punctures and cuts to the tyre side wall. There are times you’ll need to plug a puncture in a tubeless tyre and re-inflate with a bomb. You don’t want your first encounter with these problems to be out in the heat of racing. More on that next time…