Tubolito inner tubes

Earlier this year, I was excited to hear about Tubolito's new inner tubes. 

Having been a long term user of latex tubes for cross, the normal air loss and daily re-pumping are their only real down side. A more airtight alternative would be of interest.

Made from a thermoplastic elastomer called TPU, could they be a modern performance update to a traditional design?

Claiming 2x the strength at 2/3rds of the weight of a normal butyl tube, and comparable rolling resistance to latex, on paper it looks to be the case.

They are definitely light, at 52g they are 43g lighter than latex and 85g lighter than a typical butyl tube.

My LBS had just received their first batch of road tubes and showed me the YouTube videos of their puncture and snake bite tests. On seeing the rim dented by the snake bite test, I ordered a pair of CX sized tubes (I always buy from my LBS if they've given me advice or a recommendation).

They definitely feel different to regular tubes, the material has an unusual firmness and doesn't look like it will expand much, though this does mean they roll up small, taking up a lot less space in a jersey pocket if carried as a spare.

They fitted into my Challenge Baby Limus Open Tubulars and inflated just like a normal tube, their bright orange plastic valve stem feels quite different to the usual metal ones that I'm used to.

So, how to test?

I started at my usual 22psi around my local woods and all was well, they felt pretty normal to ride.

Next, I went to the roughest local gravel path I know. It's dead flat and fast but has random, up to fist sized, cobbles and stones embedded in the surface. That would be a proper test. Again at 22psi no problems.  

Gaining confidence, I dropped to 20psi, knowing that my normal latex tubes would pinch at that pressure and thinking that if these passed this test, we were on to something... They pinched... Then I discovered I had not picked up a pump that day and had a walk of shame. 

The LBS hadn't received the required special puncture repair kit yet so I tried to repair the puncture with Park's stick on patches, it worked for one ride but peeled off and was flat the next day. You really do need to buy the special Tubolito patches. 

Once repaired, a longer Battle in the Bowl training ride on the South Downs was their next outing. Again, I used my usual 22 psi and 3 hours later arrived home impressed. The South Downs Way is pretty rough on a cross bike, so again I thought we could be on to something. 

The next day the rear was flat again. The previous repairs were good, but this time there were loads, maybe hundreds, of tiny holes around the circumference of the tube. 

I was surprised I'd made it home on it, but it was too damaged to repair. 

My theory is that the tube must have been adhered to the inside of the tyre and the multitude of tiny pinches / slow punctures deflated gradually over 24 hours. 

I was disappointed to come to the conclusion that Tubolito inner tubes are not suited to my low pressure cyclo cross riding. I even looked at the video again, just to be sure that I'd seen their test dent the rim, which it had. 

I noticed two things watching the second time though;

- The tyre on test was a MTB tyre, being wider and with thicker sidewalls, the tyre is probably protecting the tube more than my Challenge Open Tubulars. 

- At the end of the video, Tubolito claim similar pinch puncture performance to a butyl tube. 

So, I can't say that Tubolito tubes are not good, they probably pinch in similar circumstances to a butyl tube. I can say that they are not as good as latex tubes with the tyres and tyre pressure I ride. 

I think that if you are happy to ride at higher pressures, then their low weight is a real advantage, you could spend a lot of money to save similar rotational weight from your rims. 

In fact, I've bought a pair for my road training wheelset and am riding them with Challenge Paris Roubaix Open Tubulars, with zero punctures or problems so far.

For road, we could be on to something!  

*UPDATE 19th September 2019* 
One of my road tubes has developed a slow leak/puncture. No matter what I do, I am unable to find it. These tubes have ended up as an expensive experiment, I'm going back to latex.