So you’ve just splashed a few grand on your first real road bike, only to get a flat. Chances are that bike runs on clincher tyres with inner tubes doing the rounds. Swapping out punctured tubes will be easy if you have the right inner tube to start with. And your first flat will teach you the valuable lesson of never leaving home without a spare. As well as a basic bike toolkit and pump to deal with a puncture.
The Inner Workings of Inner Tubes
While inner tubes and clincher tyres aren’t exactly the last word in performance and speed, they’re the first type of tube and tyres combo most new riders encounter. Most of us will be graduating to road bikes after years of recreational fun on cheaper mountain bikes or hybrids. And in the realm of road bikes, details can make a world of difference. After riding a few years with clinchers, most riders will swap out the wheels and go tubeless and never have to deal with a puncture again. Well, almost. Till then enjoy your bike, and learn to swap out a tube that’s seen better days.
Choosing Inner Tubes for Your Bike
Inner tubes cost peanuts when compared to the bike itself, so having a few spares around won’t hurt. What’s harder is getting the right tubes. Here riders have to think about sizes and diameters, the type of valves they take, and if you’re after that competitive edge, the materials they’re made of. Less of a concern is brands, but here too there are some differences. Most tubes will be made by the same companies that produce car tyres (Continental, Pirelli and Michelin are good examples), but also by bike specialist brands like Schwalbe, Vittoria and Maxxis. The latter know a thing or two about getting the right balance between durability and performance.
Inner Tube Sizes and Diameters
While sizes for road bike tubes are restricted to the standard 700c or 28 wheels and tyres, there’s more variation with mountain bikes, with 26, 27.5 and 29-inch variants sold. Most hybrids and gravel bikes also run 28-inch inner tubes but may differ in width. If you ride one of these bikes, there’s some overlapping in tube widths with road tubes, but first, check what wheels you run.
Road Tube Widths
As there are differently sized wheels and tyres for road bikes, inner tubes also differ in terms of widths. Get the wrong width tube and you’ll either have a loose-fitting tyre that will deflate on its own, or one that won’t fit the tyre at all. For road bikes, there’s a wide spread of inner tube widths, ranging from traditional sizes between 20 to 25mm, or more recent tyres sizes from 25 to 32mm. Narrower wheels will undoubtedly run smoother with the first range of widths, while wide wheels (and those in gravel bikes) take wider tubes. Things are simplified by checking the tyre sidewalls as to what width of tube fits and what won’t. There’s some leeway here and you can go a few millimetres wider (for a bit more cushioning). A tyre designated as 700x23c will naturally fit a 23mm inner tube, but also one that’s 25mm.
Check the Valves
There are two flavours here, with road bikes erring on the Presta side of things, and very rarely will you find road bike tubes with thicker and shorter Schrader valves (like the ones in car tyres). Presta valves are thin and elongated valves with a threaded screw top that’s opened to inflate the tyre and screwed down to keep the air in. The benefit is that they allow for smaller rim holes so are well-suited to road bike wheels. There’s also less weight (and road bikes fanatically keep this to a minimum) and higher pressures can be achieved. Typically a road bike inner tube with a Presta valve can be inflated to 8 bar or roughly 120 psi, or about 3 to 4 times in comparable mountain bike tyres and tubes with Schrader and what you’ll find in your car wheels.
Inner Tube Materials
As with valve types, there are also materials to consider. A road bike tube can be made of either synthetic or natural rubber – butyl or latex. Butyl tubes are by far more common, and usually cheaper. Butyl has high elasticity, so can take a range of tyre pressures and still conform to the wheel and tyre. Where they’re let down is the higher weight and greater rolling resistance so often reserved for training or leisurely riding. Latex tubes are a bit more expensive but have a few advantages over butyl. They’re much more supple and flexible, so offer better rolling resistance. And this makes them the ideal tube for racing. Another advantage is that they are less prone to punctures, due to their greater elasticity. There are downsides to latex inner tubes though besides the higher price. They’re harder to fit, and you’ll be checking the air pressure in them more often due to leaks. In addition, they need more work with punctures, but these are minor niggles if you’re looking for outright speed.