Continental

So I'm an old guy (72) been riding and racing since I was a teen. So for quite a while anyway. These are the first TPU tubes I've ever run on my bikes. I like them, it's only been a couple months but they're lighter and I think maybe roll faster than butyl tubes. I've had no flats and no problems with the valve stems working with the stem extenders my wheels require. I'd recommend them.

I bought a set of Race Rapid Dubnitals after reading their rolling resistance reviews, puncture resistance, and prior experience with 2.2 Black Chili Race Kings. I wanted a light, fast rolling, durable tire for the Whiskey Off Road 50 to attempt a PR effort and these did not disappoint! Only regret I have was not getting them in tanwall. :-)

Dubnital race rapid 2.4. SW AZ, desert, mostly loose over hard pack with plenty of chunky rock conditions. As expected these are fast tires confirmed in testing. As a rear tire they have very good traction on punchy loose climbs and noticeably better than say a Recon Race. As a front tire they are good but they don't give any warning when they're about to cut loose. Push it too hard and it's gone. For me they like as low a pressure as I can run without whacking rims. They are narrower and a more rounded profile than the equivalent Maxxis tire size.

These tires roll fast enough for me to keep up with a friend on a road bike. I was putting in more effort but I was extremely impressed with the speed.

I am also impressed with the off-road capabilities of these tires on all types of terrain - loose over hard pack, shale, pebbles, larger rocks, sand, etc. Probably not the most stable tires in the world but the tradeoff for their speed is well worth it. Also, the side / edge knobs have saved me numerous times.

Unfortunately, I've had two tires ruined with non-save-able punctures in the last three weeks. The first was some debris on a road, likely something metal and sharp. The second was on a trail full of rocks and sticks. I would gives these Dubnitals 5 stars except for the two tires I had to put a tube in to finish my ride and toss afterwards :(.