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We’ve seen a curious explosion in inner tube options in recent years, with multiple iterations of butyl, latex, and now polyurethane materials all claiming to deliver tangible performance benefits. UK outfit Aerocoach has just released its latest round of rolling resistance testing, and while some of the most recent options did pretty well, high-end latex still comes out on top.
Different isn’t always better
Polyurethane is hardly a brand-new material for inner tubes (Panaracer debuted its Greenlite tubes back in the 1990s), but reformulated versions of the polymer have re-emerged as the alternative material of choice. Tubolito arguably kicked off the trend with its distinctive orange color, but German company Revoloop has grown increasingly popular, and Schwalbe recently jumped into the polyurethane fray with its Aerothan range.
Polyurethane proponents tout a number of benefits, including extremely low weights, excellent air retention, and impressive puncture resistance. Tubolito’s disc-specific road model is said to weigh an incredible 23 grams, for example, and Schwalbe claims its Aerothan tubes are twice as hard to puncture than latex or butyl, and more resistant to pinch flats, too.
But what about rolling resistance?
Aerocoach’s earlier round of testing included both of Tubolito’s inner tube models, finishing with mid-pack results relative to ultralight butyl and latex. As compared to the best-performing ultralight butyl inner tube (the Continental Supersonic), a pair of Tubolito standard inner tubes requires 2.7 watts more power to maintain 45 km/h during the company’s roller tests. The thinner-walled Tubolito S model is 1.5 W faster, but still 3.4 W slower than the top-performing latex inner tubes.
There’s clearly something to be said for how the tubes are made, though, not just what they’re made from.
Revoloop tubes did a little better, posting a 2.3-W advantage over the Tubolito S tubes, and falling behind the best-in-test Vredestein latex tubes by a scant 1.1 W. And those new Schwalbe Aerothans? They landed in between the Tubolito S and Revoloop tubes, but are still impressively efficient with the Revoloops boasting a minimal 0.5-W advantage.
But there’s still more to it than just rolling resistance
Going strictly by Aerocoach’s numbers, then, it seems clear that if you’re hyper-focused on reducing your rolling resistance, and still prefer to run inner tubes, high-quality latex tubes are the way to go. According to Aerocoach’s testing, it doesn’t seem to matter too much which latex tubes you run, either, with Challenge, Vittoria, and Vredstein models all landing within 0.1 W of each other (Michelin’s Aircomp latex was the outlier, requiring an additional 1.4 W at test speed, but still coming in ahead of all the butyl and polyurethane samples, save for the Revoloops).
However, there are other factors to consider as well.
If you’re a die-hard weight weenie looking to shave every bit of mass, for example, those Tubolito S inner tubes can lop off 100 g relative to latex. Polyurethane tubes also offer better air retention than latex, which need to be topped off almost daily, and if you take manufacturer data at face value, these fancy new polyurethane tubes are less likely to puncture during a ride, too.
In other words, for a small rolling resistance penalty relative to latex, polyurethane tubes seem to have a lot to offer, albeit with a hefty initial investment. Retail price for most of these polyurethane tubes is roughly double that of latex tubes (which are already more expensive than even ultralight butyl tubes). They’re thankfully repairable if you get a flat, although they do require dedicated patch kits for a proper fix.
So which tube material is right for you? Butyl is still obviously the least expensive, and latex is still the fastest. But polyurethane is clearly gaining ground, and if prices can start creeping down some, we might have a legitimate fight on our hands.
What type of tubes do you prefer, and why? Let us know in the comments below.