Matt
Question for you,
What are you calling thorn proof tubes?
I am running these tubes on my e bikes:
These were the best HD tubes I could find at the time.
So far, very good results, with Flat Out + these tubes.
Tia
Well of course nothing in this world is truly thornproof... -resistant but not -proof.
The answer to this question is a moving target. It depends on what day it is, almost, and what wheel we are talking about. Remember also I use Presta valves on almost everything which changes things up quite a bit in terms of choices out there.
Sunlite makes thorn-resistant tubes that are pretty thick. So does Duro. But the Sunlites on occasion get ding'd for the valve being not so well affixed. This is because, I think, people are using them undersized which is the opposite of what I do. An undersized tube on a powered wheel will slip and the valve might tear clean off. Oversize the tube instead and not only will the tube fix firmly in place on the rim, it will be stronger because it is not stretched thin like a balloon.
As a general rule I am trying to use Schwalbe Air Plus tubes these days. These tubes are about halfway between a thornproof and a regular tube in terms of thickness. And you get a quality tube.
For fat bike tubes, I stick with Vee 26x5.05" tubes. They have two versions. One is lightweight and thats NOT the one I use. The standard weight tubes are about 1.5mm thick. I also make sure I buy presta tubes with removable valve cores so I can more easily inject Flatout so that makes my tube choice list smaller. Back in the day I used Kenda fat tubes, which were pretty thick, and used an injector thru the tube rubber to get the sealant in.
I have seen the Bakcou tubes, and they are relatively new on the market as fat thick tubes used to be considered too heavy. However the Bakcou's are not in a truly fat size and the last thing you want to do is use a 4.0 tube on a tire larger than 4.0. A 4.0 tube would be fine on a 3.0 to 3.5 tire though. The BackCou 20x4.0 tube is off my list because of its valve not screwing down, so on a powered wheel the stem will slip/walk. I use the Schwalbe Air Plus 'American Valve' that is a schraeder valve with threads and a nut that goes all the way down.
If I didn't know what I was buying in advance, I would spend time looking for a tube with the thickest rubber I could find, with a valve that fully screws down onto the rim that is also long enough to get thru my double-wall rims. What I end up with is going to vary depending on whats on the market.