santa fe 2926 

Decided to try some TPU tubes. First I got some Schwalbe Aerothan from BikeInn, for 23-28 tires, 41grams. Running Veloflex Corsa Race 25’s, psi at 95-100. Two nice rides of 45 and 35 miles. Intrigued by the technology, went for some Cyclami tubes off Amazon, with a steel valve, only 38g. Thought the steel valve might last longer. Anyway first ride with Veloflex Corsa 28’s, 80 psi. 18 miles and the front tire exploded, the hole being next to the end to end seam. Brought a butyl tube and my normal flat kit, but then I had nothing if the rear tube flatted. Made it home. Next day returned the tube to Amazon via Whole Foods. When I got home that afternoon, the rear tire was flat! Today the replacement arrived. Two flat tubes on one ride! Before mounting, I carefully pumped enough air to check for leaks in water, easy installation as they are so slippery, and the 28’s weren’t new. Think the new one and the flat are going back for a refund! On todays ride the with Aerothan tubes, I carried 2 butyl tubes and repair kit, to be safe. Any suggestions would be appreciated.

The blow out right next to end to end seam

The 1970 Roberts

Not recommended

momoman

Read my comments and the other comments in this thread:

Your choice of light inner tube

Basically, I really like the tubes but there are Quality Control issues with the Chinese made tubes. I’ve had 2 brand new tubes leak - they lost air over 1-12 hours. The ones that don’t leak from day one are great! I carry 2-3 spare TPUs and a TPU patch kit with glue. I bought a dozen so I have plenty of spares.All my friends are slowly converting over to Ridenow TPUs - they are $6/ea or so.

kunsunoke 

Cyclami tubes have mixed reviews on Amazon. The text descriptions offered up by the reviewers were particularly revealing.

The failure rate you describe seems typical for PRC-manufactured items. Not a good idea for clinchers, where a tube failure in the wrong place (fast downhill) can be catastrophic.

icemilkcoffee 

I also had two unexplained tears in TPU tubes recently. They are almost certainly the result of pinching while mounting. Because of how thin they are, TPU tubes are very prone to getting pinched between the rim and the bead. This is especially the case with 'open tubular' style tires like the Veloflex, because the tire itself is all floppy and shapeless and reluctant to get seated. The best way to mount TPU tubes is the get the first bead in, and then get half of the second bead seated. And then pump the tube up so it's filled with air, but not pressurized. Now carefully seat the rest of the tire, taking care to push the tire and tube away from the side you are trying to seat. As I said, it's not easy with open tubulars.

esasjl

Very nice CR. I've not had any problems with Aerothans across a number of sizes. The plastic valve stems have been fine.

jadmt

i have a set of aerothans waiting to go in when I replace tires in the next couple hundred miles but the stems have me nervous

santa fe 2926 

I use a Zefal floor pump and a separate hand held psi gauge. I try to hold the stem with my fingers when I push the pump head or air gauge on.

santa fe 2926 

The drive side. Serial number is 150, some on the Roberts group said that would be 1970.

esasjl

I think three figure frame numbers are pre-79. The info is on the web somewhere but not sure where. This may be useful.

santa fe 2926 

Joined the Roberts group a while back, my post numbers are 813, 816, and 818. That is the source of dating the #150, as around 1970. Cheers!