If you use a wheel/tyre system that takes inner tubes, a new white paper from Vittoria explains how to choose between butyl, latex and TPU (thermoplastic plastic) options.
The Bicycle Inner Tube Materials and Applications white paper has been written by Ken Avery, Vittoria’s senior vice president, product development, and it covers the three main types of inner tubes used today, including the strengths of each.
It must be pointed out, Vittoria has recently launched its Ultra Light Speed TPU inner tube, although it offers butyl and latex tubes too.
Of course, many riders have moved on to tubeless setups these days, but the white paper points out that even these systems can fail due to expired sealant or large holes that the sealant can’t fix, for instance, so carrying a backup inner tube is good practice.
“[Butyl rubber] is an excellent choice for inner tubes, as it exhibits quite positive shock absorption characteristics for durability while returning low moisture and gas permeability to maintain internal pressure,” says Ken Avery.
He points out that black butyl inner tubes are by far the most common kind found on new bikes and they’re easily patched if you puncture. You can get lightweight butyl tubes, thicker-walled versions to minimise the chances of puncture and self-sealing ones that contain a liquid that’s designed to plug small holes automatically.
However, butyl isn’t especially light and the rolling resistance is higher than that of other options.
“The level of elasticity of butyl rubber is slightly lower than with some other tube materials, which contributes to increased internal friction between the tube and the inside of the tyre, causing negative effects on rolling resistance in high-performance use,” says Ken Avery.
Latex has certain benefits as a material for inner tubes compared with butyl.
“As the material allows for increased flex and stretch, the propensity for the tyre to deflect from road surface imperfections is reduced, resulting in an overall reduction of rolling resistance,” says Ken Avery.
“Adding to the allure, the natural flex of latex, and the resulting increase in performance does not come at the cost of weight, as latex inner tubes are typically on par, if not lighter than the lightest ultralight butyl inner tubes.
“The highly elastic trait of latex is also what makes it potentially less prone to punctures, as oftentimes the material will stretch around the offending puncture item (nail, glass, thorn, etc), rather than be pierced by it.”
On the downside, latex inner tubes don’t hold their pressure as well as butyl ones and patching latex can be difficult, but they’re still “an easy and affordable upgrade for any performance-minded rider”.
TPU (short for Thermoplastic Polyurethane) inner tubes are a much more recent alternative. As a material TPU has the characteristics of both plastic and rubber – head mouldable like plastic, flexible like rubber. Why would you switch to TPU?
“The reasons are many, but chief among them is the impressive reduction in weight and rolling resistance, while at the same time increasing puncture protection,” says Ken Avery.
“The highly elastic TPU material raises performance to levels previously unreached with either butyl or latex while returning a further reduction in punctures, all while also increasing air retention.
“TPU not only improves upon the performance of latex but also cures the main setback, by providing a system which is less susceptible to lose air over long periods of time.
“TPU inner tubes have the ability to reduce environmental impact during manufacturing through a reduction of raw material and increase sustainability at end-of-life as they can be recycled for other uses.
TPU inner tubes are more expensive than other options but Avery agrees that they are good value in terms of increased performance.
“The dollar spent per watt saved in rolling resistance is nearly impossible to beat when upgrading to TPU tubes, especially when compared to butyl alternatives,” he says.
“If you are a rider who seeks the ultimate in performance, and appreciates the simplicity and hassle-free installation and maintenance of a tube-type system, then TPU inner tubes are likely the right fit for you.”
Vittoria’s white paper shows several charts that compare the characteristics of the three inner tube types.
This one shows weight comparison data between butyl, latex and TPU. Like the charts below, it’s based on Vittoria’s internal laboratory data.
Rolling resistance comparison data.
Durability comparison data.
Air retention comparison data.
Cost comparison data.
This table compares the speed, durability and weight of the three type types.
What do you think is the best type of tube for the riding you do? Let us know in the comments.
Mat has been in cycling media since 1996, on titles including BikeRadar, Total Bike, Total Mountain Bike, What Mountain Bike and Mountain Biking UK, and he has been editor of 220 Triathlon and Cycling Plus. Mat has been road.cc technical editor for over a decade, testing bikes, fettling the latest kit, and trying out the most up-to-the-minute clothing. We send him off around the world to get all the news from launches and shows too. He has won his category in Ironman UK 70.3 and finished on the podium in both marathons he has run. Mat is a Cambridge graduate who did a post-grad in magazine journalism, and he is a winner of the Cycling Media Award for Specialist Online Writer. Now over 50, he's riding road and gravel bikes most days for fun and fitness rather than training for competitions.