Thinvik 2PCS TPU Inner Tube Upgraded Durability for Road Bike 700cc x 18-32, 33-50c Bicycle Tube 65MM 85MM Length of Presta Valve (One Pair)

Easiest and most cost effective way to drop over 100 grams of rotational weight for each wheel! I also love that these have the metal valve instead of the plastic one you see on most other TPU tubes. They were easy to install and provide an IMMEDIATE benefit. I did this and tires for a combined overall weight reduction of 500 grams.

Feeling a bit reserved on this review but will update after a few months. I have 350 km on these tubes and have had no issues so far.

First, although the inner black boxes in my order state a weight of 36g, the product spec grid as well as a photo of the product on scales shows these 700x18-32c tubes as 42g, which is also what they weighed on my scale. This includes the rim nut and Presta cap for the weight weenies out there (40g without those items). The valve cap is metal, which is a small thing but a nice feature as I feel it's a bit more robust than the plastic caps.I've used earlier Thinkvik tubes and I appreciate that they've revamped their product - note the "upgraded durability" in the description. These tubes are a little thicker than others I've tried, and they feel more robust as a result. The extra thickness means they're less likely to puncture. So far, after a few hundred miles of riding, I've had no problems with these tubes. The threaded metal stem allows me to lock the stem to the rim, keeping it from tilting or twisting while I inflate the tire. That reduces stress where the stem joins the tube - a point where tears can occur. There's already extra material there, but the threaded stem gives a bit more assurance. Unlike some plastic valve stems, the metal stem works well with every hand or floor pump I tried. Also, the airflow was unrestricted and it inflated as easily as a common butyl tube. The vale core is not removable, but that's hardly a problem as I've never had a core fail.I was surprised at first not to find any patches included. Previous tubes have included them and I've found applying the patches is much easier than with butyl tubes. However, I suppose Thinkvik's recommendation not to patch the tube if it's punctured is erring on the side of caution. If the glue on a patch fails while you're out on a ride, most people would blame the tube and not the patch.

I like the aluminum valve stem, easy to install. Time will tell how durable they are. I did add tire liner as additional layer of protection, and still lighter than butyl tube.

These are decent TPU tubes which are vastly lighter than conventional. And much more compact to pack as a spare. This particular model is good because they use normal, threaded metal valve stems which are much better than the plastic tubes some use. The nut can hold it in place and the pump valve stays put better