A few posts ago I bemoaned spending £000’s of pounds on an aero bike for marginal gains. That’s not to say I’m adverse to trying new kit to get a benefit if I think it’s worth the investment. In that post I explained how I’ve spent £850 on a 50mm deep section carbon wheel + tyre upgrade which, for me, gives me a more bang for my buck than, say, a frame with hidden cables, for example.
My latest bit of research lead me down the rabbit hole that are TPU Tubes. The (relatively) new kid on the block amongst inner tubes. They’re an attempt to bridge the gap between speedy, superlight latex tubes and the heavier more reliable standard butyl.
TPU (Thermoplastic Polyurethane) inner tubes are made from a specific type of plastic known for it’s durability, flexibility, and puncture resistance. They are light too. In comparison, latex are a little lighter but are probably the fastest (least rolling resistance within the tyre) out of the three types but do lose air very quickly. Traditionally they have always been used for racing only, for example, used in tubulars. Remember them?
On the other hand you have traditional butyl inner tubes which are heavier and create more rolling resistance. So, although they are not as light as latex, TPU are still much lighter and faster than butyl with the bonus of being a bit more puncture resistant. So TPU tubes, on paper seem like the perfect compromise.
So I decided to try them on my road bike. Again, scanning the web and much like choosing my USB mini-compressor recently I found loads of brands. Mostly unknown Chinese but some I have seen before. I was swayed by cost and reviews and plummed for 4 x Cyclami TPU tube for my 28mm Continental GP5000’s which came with free tyre levers as it happens. Total cost £22, so not too expensive either.
When they arrived and I unboxed them, firstly I noticed they are ridiculously light and small. The very flat profile of the plastic allows them to be rolled up very tightly. The plastic feels almost too thin and brittle to expand akin to a plastic carrier bag but fitting them was no less hassle than a standard tube taking the usual care not to pinch them.
I fitted them a few days ago and left them for a couple of days pumped up and air retention was fine.
Last night was my first ride out on them. I rode 50km, mostly on the Saturday Bash route so roads were familiar and I could try to compare. I averaged just under 20mph solo, which given it was quite windy, I felt was quite fast. From a feel point of view they definitely feel more snappy. If you ever raced on tubs and remember pumping them up hard, they felt like that, really responsive. Now….whether that translates to straight-line speed I don’t know 100%. My gut feeling is they are marginally faster, that’s just an anecdotal conclusion from last night’s ride but even if they are the same as my standard tubes (I can’t imagine they would be slower), they feel better so I’m going to stick with them. And as they’re not too expensive I’d recommend you try them too.
Based on that they may seem like a no-brainer but do bear in mind, if you’ve invested in a mini-compressor and you do use one as a spare, you will need a flexi-tube to connect the compressor as a direct connection risks melting them. I’ve just kept my butyl tube as a spare. I wouldn’t recommend using them on rim-brake bikes either.
And I suppose the other question is can they be repaired? Yes, with a specialist kit. The tubes are more expensive than butyl so repairing them maybe an option and it’s just better than chucking them away. I’ll dive into that more when I need to.
Now I need to see if they are viable on my gravel bikes, but for now, keep pedalling!
Adios