Contents of this article
What is a TPU hose?
TPU does not require natural rubber, production takes place in Europe and the material is 100 per cent recyclable. The ecological footprint of production is significantly smaller than that of standard inner tubes. What every TPU tube also has in common is that it weighs much less than a butyl tube (from 23 grams!), has a much smaller pack size, rolls more easily than butyl (but not quite as well as latex) and is still more puncture-resistant. TPU tubes even beat tubeless systems in terms of weight and roll just as well.
TPU inner tube road bike experience
However, the great laboratory values of TPU products are sometimes offset by negative user reviews. There are complaints that the tubes are defective ex works or start to lose air quickly. These may be outliers, but we have also had such cases in our editorial environment. With prices of around 25 euros per hose, such quality problems are more serious than with the cheaper butyl counterparts. Holes are also harder to find, as the hoses can only be pumped up to 0.3 bar outside the cover; if they are pumped up more, the material can deform plastically and burst.
Patches are a makeshift solution
It is also difficult to permanently repair a TPU tube. The valve stems can also cause problems, as they are also made of plastic in TPU inner tubes and are therefore less robust than the usual metal stems. The valve inserts cannot be tightened as well and therefore loosen more easily. Leakage problems at the stem are one of the known problems with TPU. Tubolito therefore glues the valve inserts in place. This solves one problem, but creates new ones. This is because the valve length can no longer be adjusted as usual using an adapter. And where the inserts can be screwed in, details are also important: Schwalbe has special valve extensions with stop and adapted seal for its Aerothan TPU tubes in its programme.
TPU manufacturers also rate the compatibility with sealing milk differently. Schwalbe advises against the combination and recommends cleaning tubes after they have come into contact with sealing milk. Tubolito, on the other hand, has no reservations.
Despite all the criticism: Compared to extra-light butyl tubes, which are super-sensitive, TPU tubes are a clear improvement; the minimal pack size is also a big plus. In the following, we show you how to handle TPU tubes correctly and how to repair them in the event of a defect.
Advantages and disadvantages of TPU hoses
Tubes made of thermoplastic polyurethane (TPU) weigh little and roll well. Various manufacturers offer TPU tubes. All TPU products have the following points in common:
Advantages
- light
- Tiny pack size
- roll well
- puncture-proof
- good-natured failure pattern
Disadvantages
- expensive
- Patching is not a permanent solution
- Sensitive valve stems
TPU hose particularly puncture-resistant
Fitting the TPU hose - instructions in 6 steps
TPU hoses are easy to fit. They take on a firm shape even at low pressure, making them easy to place in the casing and less likely to be pinched during installation. The most important detail when fitting: only fill TPU outside the cover with a maximum pressure of 0.3 bar. Otherwise the hose may be destroyed. The installation of TPU hoses is shown in the following series of pictures:
Mending a TPU tube: how it works
TPU is similar to butyl in terms of handling, but requires a different repair material. The standard patches for butyl tubes do not adhere to TPU. The manufacturers offer two repair solutions: with a special adhesive (Pirelli, Tubolito; both with Campast adhesive from TipTop) and with self-adhesive patches (Revoloop, Schwalbe). In laboratory tests, the bonding worked less well than with butyl, but was ultimately successful. The self-adhesive patches seem more practical as a quick solution for travelling. The long-term stability of TPU patches is predominantly rated negatively by users. In principle, defective tubes should therefore be replaced. The repair kits cost between 4.95 euros (Tubolito, 10 patches) and 7.95 euros (Revoloop, 3 patches). The following series of pictures show how the repair works:
With adhesive
With self-adhesive patches
Supplement 2/2024, Sandra Schuberth
Recycling TPU hoses
Every inner tube comes to the end of its life at some point. For classic butyl inner tubes, Schwalbe has introduced a recycling process in 2015. After a lot of research and development, it has even been possible to recycle tyres there since 2022.
The Viennese company Tubolito, founded in 2016, also wants to conserve resources through recycling, among other things. The TPU material used in Tubolito hoses is 100% recyclable, according to the manufacturer's website. The problem is often to return used products in order to close the cycle. How do used Tubolitos get back to the company's headquarters? The company has partners in Austria and Germany - and of course Tubolito's customers are in demand. Used Tubolitos or other TPU tubes can be handed in free of charge to participating recycling partners. The partners collect the tubes and send them back to the company. The tubes are then turned back into tubes or other TPU products.
Recycling partners are easy to find on the website tubolito.com.
TPU hose recycling at Tubolito in brief
- Take your used Tubolios or other TPU hoses to a recycling partner
- Tubolito collects the hoses at its headquarters
- The recycled tubos can be used to create hoses or other TPU products again
