2-Pack 700x 18-32c Ultra-Light TPU Inner Tubes with 45mm/65mm/85mm Presta Valves for Road Bike, ONLY 33g

Light weight . Puncture resistant. The Valves leak air too quickly. Checked that they were tight added some plumbers tape to threads stopped leaking.

First attempt to place 80mm stem tube, pumped up to 4-5psi, placed onto rim making sure it was not caught any where, inflated tire to about 20psi, then deflated it, then pumped up and at about 80psi, tube ruptured.Second tube would not hold any air. Whether it was the valve, or the tube itself, it was a disaster. Will never buy this product again!

These are light, and I easy to store in the saddlebag. I like the fact that it includes a patch kit. Pay attention to the inflation pressures because with butyl tubes on my road-bike I inflate to 90psi and the TPU I inflate to 65psi, I believe the max is 72psi. To my surprise my Cannondale CAAD10 road smoother and faster (Strava).

Love the lightness. There is an issue, but not a major problem. You will need to refill them every few days.

I’ve only done two rides on them but they were both 70+ miles back to back days. Not sure if it’s all in my head or if the rolling resistance is truly better with these. But it seems I can ride 1+ mph faster with the same effort as before with butyl tubes. So far I’m impressed. See how well they hold up.

One of 2 tubes developed leak after 3 rides of 25 miles. Under water exam revealed leak occurred at interface between the blue TPU and the black material used to coat the stem. This position is indicated by the black arrow in the review photo. I have not yet dissected it but it appears that there is an 0-ring at the base and that the TPU is tighted around to make a seal. For the remaining tube I will be using pliers to hold the stem any time I am messing with the stem, as in adding air or tightening the stem core.

I switched my spare tubes to TPU to reduce the size of my saddlebag. I normally run latex and know how to be careful when changing tubes (never damaged a latex tube while changing them).I hit a rock while riding and flatted. It was very obvious the flat was due to a rock, but I inspected the tire before installing the TPU tube. I was very careful to ensure a good tube change and I felt like I didn't do anything sloppy that would result in a damaged tube.I used CO2 with a flow control and slowly increased pressure up to what I thought was a good but not over inflated pressure. After a screwed in the value, I noticed that there was a leak (I assume from the valve stem area).Bummer. I installed my other TPU tube and was successful. Since I no longer had a spare tube, I decided to abort my ride. After getting home, I put two butyl tubes in my saddle bag, reinflated the TPU tube, and headed back out for more miles. After 20 miles or so, I noticed my back tire was squishy. Slow leak. replaced the tube with my butyl spare and had no problems after that.So, both of my TPU tubes in the 2-pack failed on the same day. It is only one data point, one user experience. I was skeptical of the other one-star reviews for this type of issue. But these inflation issues seem very common for most TPU tubes/vendors. Some seem to think a metal valve may work better than plastic, but I am not sure I want to put the security of my ride into the hands of TPU again until QC gets this issue figured out.

I really had high hopes for these tubes, and I got these to replace the old style rubber tubes. But these are terrible because you have to air them up everyday. About 10 psi is gone and before every ride I have to check the pressure to see how low it is. It’s more frustrating than anything. Unfortunately I have purchased another brand because these are not worth the hassle.