squirtdad

I decided to try TPU tubes based on the benefits

I used the Rene Herse 20-32 tubes with Rene Herse 32mm ultralight tires

Installation was easy, not much different than butyl, and definitely easier than latex

I was stoked and off on my first ride.

2 miles in the front tire got a flat.

what was surprising and disconcerting to me was that flat was sudden, full to riding on rim instantly.
I was able to stay up but barely, as I had just gone maybe 150 feet from a full stop
Had I been at any sort of speed, this would have been a hard crash

the tire/wheel combo had gone 800 miles since new without a single flat and I checked rim tape and tires before installation

has any one had a similar experience?

I did a road fix with a butyl tube..... the TPU are so light, that road replacement in the wind could be an issue

I will also say that no one should plan on patching a TPU tube on a ride.
Just finding the hole has been fun, I pump up the tube and it deflates so fast, that it is hard to fine the hole....(no rips) I will go soapy water next, but put tube aside to let my blood pressure go down

this posted as info, not as an indictment of TPU tubes. I think myself I will go back to my tried and true Conti race lite tubes

13ollocks

I've always heard that, because TPU isn't "stretched" like butyl or latex, it doesn't puncture explosively. What did the hole in your TPU tube look like, when you finally found it? IME with butyl/latex (I've never used TPU), catastrophic flats are usually a result of a gash or significant puncture.

icemilkcoffee 

I find that TPU tubes can easily get pinched during installation or removal. During installation, when you are trying to seat the last section of the bead, you could easily trap the TPU tube between the bead and the rim. That is why when you get to that stage, you need to inflate the tube slightly (instructions say 5psi), and then use your free hand to push the tire and the tube away from the exposed bead that you are trying to seat, while you try to seat the bead with your other hand. During removal, if you just jab your lever in- it's easy to have both the clingy TPU tube and the bead caught on the lever. Instead just jab in as much of the lever as needed to pry up the tire. Now pry the tire up and down several times until you can see that the tube is no longer clinging to the tire. Now remove tire as usual.
Also- patch repair of TPU tubes is always an extremely iffy affair. I've had maybe 50% success and honestly I haven't found the magic formula yet.

genejockey 

Pinch off half the tube, inflate. If it inflates, the hole is in the part you pinched off.

I am curious to know what caused it. Make sure to let us know if you figure it out!

squirtdad

That is my fun for the evening......after an afternoon ride and finishing a video of my last kayak fun (bumpy (for me) water off of Moss Landing)

I will post with pics and updates, especially if it was user error

chaadster

Hmm, I think something else is going on. If it is deflating nearly instantly, how can it be a pinhole so small you can’t see or find it be the culprit? That doesn’t add up. My guess is that it’s more likely something like the valve pin not being screwed down tightly, or maybe a loose valve core. Something bigger than a pinhole. Schwalbe actually tout their TPU material prevents sudden air loss when punctured; TPU composition certainly varies across brands, but it’s generally understood that TPU doesn’t rip at the puncture site, unlike latex, so unless the initial puncture was big, a small puncture won’t get big after the fact.

I’ve been running TPU for over 3 years now, mostly Schwalbe Aerothan, but also RideNow TPU in both 24g and 36g. Aerothan are my favorites if only because of Schwalbe’s reputation and their claims about Aerothan inspire confidence. The RideNow are attractive because of price, which is quite low, and while the 24g gave me lots of trouble with weird overstretching near the pedestal of the valve stem (I threw out 4 of those after each failed the same way) but the 36g have been fine. I’ve patched both Aerothan and Ridenow successfully with just a little degreasing of the patch site and using regular, Lezyne self-adhesive patches.

It’s impossible to understand anything talking about frequency of punctures, as that just mostly comes down to luck (or lack thereof) so I won’t say anything on that.

I’ve got 2 pairs Aerothan in service and 2 pair RideNow 36g in service right now. I think the total package with TPU— puncture resistance, lightweight, fast rolling— makes using any other tube seem silly, especially at the RideNow prices, which are scarcely more expensive online than what you’d pay for butyl in a bike shop. I went road tubeless 10 years ago, and while I prefer tubeless for the extra security of the sealant, TPU is a very, very strong contender, and I don’t feel like I give up much on my TPU equipped bikes compared to my tubeless bikes. When it comes to convenience, though, TPU takes the cake.

Outrider1

What a well thought out and expressed response!

Rick

I purchased three Aerothan tubes and installed two of them in my bicycle. My bicycle set unused for several months. The tires were totally flat, when I went to use it. I aired them up and one of them wouldn't hold air. The other one went the same way day's later. I will stick with the rubber.

prj71

You guys with flats are pinching them during installation. User error.

I've been using Schwalbe Aerothan for 2 years now with zero flats..

chaadster

TPU holds air just as well as butyl. I mean, they both sit around unused in boxes for months, so I’m not clear on why sitting unused in the tire would be a risk factor for TPU more than butyl. What was the source of the leakage? TPU are all bonded together at some point (to close the circle), so maybe that could be a failure point, but I don’t understand why it would be more inclined to fail when sitting rather than rolling, and we just don’t hear about that being a failure point generally, so that’s why I’m curious how yours failed.

jadmt

ditto I have two sets of wheels with different style tires and both sets have Aerothan tubes and one set sat all winter and each tire was still at around 60psi from mid 80's.

cyccommute 

You are not alone. My first installation of TPU tubes didn’t even make it to the first ride. Nor did my second. Since I clock my tires, I was able to identify the punctures that were due to very, very, very small objects that were embedded in a set of older tires. They weren’t long enough to puncture butyl tubes but they were long enough to puncture the far thinner TPU tubes. To make matters worse, the provided stick on patches did absolutely nothing to seal the tube. I had 3 or 4 more flats on the road with the two tubes that were patched before I finally got a proper patch kit for TPU which did work much better.

I will say that your observation that this is not a repair to do on the road is spot on. The instructions say to clamp the tube for 30 minutes.

squirtdad

Did not get to the promised leak hunt.....tomorrow

I am not rulling out operator error at all. some time with the tire on the kitchen table and some soap solution will tell

genejockey 

I just use a washtub full of water, like trying to drown a snake.

bblair

I really wanted this to be a thing, but the miniscule speed increase surely does not justify the number of flats you are having. Too bad as I was ready to buy.

RB1-luvr

I had a catastrophic flat on my tour bike this past weekend. The replacement butyl tube I had had the wrong stem length, an error overlooked by me. Luckily, I also had a cheap Alexi Press TPU tube in my pocket. Its operating range was listed as 18-32c. My tires measure 39.2c installed. That tube and a candy wrapper tire boot got me four miles to a bike shop for a new tire and tube. That's my only experience with TPU tubes. I will continue to carry them for emergency purposes.

chaadster

It seems so apropos of the current American cultural zeitgeist that we can have people who've been running TPU successfully for years, people that have patched TPU without trouble, major tire brands like Schwalbe, Pirelli and Vittoria making TPU tubes, and that we have at least one TPU manufacturer who not only claims the material makes "punctures impossible during normal use," but backs it up with a 1 year warranty against flats, yet we folks who think it's perfectly smart to conclude TPU isn't ready for prime time because some yokel couldn't even manage to install one properly. It's pretty crazy, but honestly, what isn't anymore?

icemilkcoffee 

Wait... Snake can swim!

mihlbach

I have been using TPU tubes for years and have even converted a number of friends. I find them completely dependable, however they are not fool proof. If you treat them like heavy thick butyl tubes, you will fail.
If you are accustomed to butyl, there is a learning curve to successfully using TPU.

A TPU tube is thinner and more pliable than a butyl tube, making it more vulnerable to getting pinched during initial installation, and a TPU tube can be punctured by small sharp objects already embedded in the tire that would not fully penetrate a thicker butyl tube. They require more care during installation. Check your tires for foreign objects (as you should anyway), and use care when seating/unseating the tire.

If installed correctly, they hold air as well as butyl and puncture no more frequently. The few punctures I have had with them have all resulted in very slow deflation and the punctures, all nearly microscopic pinholes, were exceptionally hard to locate. On a couple of occasions the leaks were so slow, I simply topped off the tire pressure mid-ride.

I have only been able to find punctures by submerging in water and looking for tiny bubbles. This makes them very difficult to repair in the field, but the solution is to ditch the patch kit and carry more than one tube with you. Patch your punctured tubes after the ride. They take up very little space and multiple TPU tubes can be stowed in less space than occupied by a single butyl tube. I have patched numerous TPU tubes (post-ride) without fail, but again, if you expect to use the same methods that you use to patch a butyl tube, you will fail.

cyclezen

Have to echo posts of users with success and pertinent comments on use of TPU. I've had a solid year of TPU, with no issues.
Recognizing the light nature of the material and importance of proper installation is important.
Important is to have a clean surface/interface between the tube and both the tire and rim. Didn't take long to realize that 'dirt' , no matter how small, inside the tire or somehow attached to a tube - butyl or TPU, would eventually cause a hole/flat.
I have dealt with a rim with a v-small sharp edge at the rim joint, and a tire with a small section of wire belt having a sharpish bump, both cause flats... with butyl...
Both needed 'work' to eliminate, when recognized.
Another issue found, are sharp edges at the rim valve hole, which can wear thru the tube/valve area. For many decades now I have placed a cut section of tube, with a hole small enough to allow the valve thru, around the valve area. Has eliminated any possible valve tear issues.
I have NEVER used (in 58 yrs of riding) those small collar screws supplied with tubes, never used with sewups either - useless and unneeded, if you're running at pressures which assure no pinch flats...
TPU, not a miracle, just very good improvement, IMO. I still have bikes with butyl and fine there also... But TPU will continue to be my future for 700c roadbike use.
Ride On
Yuri

rsbob 

Recently installed a pair of TPUs, not aware of the proper protocol, and had no issues. But then I always put a little air in my tubes to help prevent pinching. Have ridden them on GP5000s for about 500 miles with nary an issue. The combination feels as fast as my Conti 5K tubeless setup on another bike. I am a convert.

chaadster

As you discovered, the “proper protocol” is exactly the same as you’d use for butyl, latex, or any other innertube. There is no TPU specific protocol.

squirtdad

I object to your calling me a yokel and the tone. You make assumptions that are not valid and have no idea of my experience or skills

If you read my original post carefully you will note this was sharing my experience so far and I called out that it was not an indictment of TPU
I am generally curious if other people had the same manner of fast flat.

I am experienced and installed the tire carefully. I am 98% sure that I did not install it such that is has a pinch flat.
I have never had a pinch flat before with hundreds butyl tubes I have installed over the years Possible one with a latex tube....

No tool was needed to seat the tire and the tube was in the tire

Any way i will follow up with pictures of the the hole or holes and patching. So far no rips have been found

chaadster

Ah, I’m sorry! I was not referring to nor thinking of you (after all, you did get them installed and out for a ride), and rather was speaking in a general sense. I do understand I might not have made that perfectly clear, though, so please accept my apology.

Don’t forget to check the valve is properly tightened, both pin and core.

squirtdad

thanks.... valve core is something I check, have had too many tubes with loose valves out of the box....even carry a tool with me in my on the bike kit