I just got a pair of Tannus tire inserts for my 26x4.8 fat tires, along with a set of 26x3.0" tubes, as per Tannus info.
I have a problem with the tube size,
I inserted the tubes inside the inserts, and gently pumped them up, to make them into a round diameter,
the tubes over lap by 2-3" (Z shaped), when inside the tire inserts, I don't believe that these tubes are the correct size.
These inserts/tubes are sitting where they can be gently warmed to a nice round shape, by the sun shining thru the window.
The tubes measure about 78" around their outside diameter, with just enough air to barely make them into a round shape,
and I believe that the tubes will have severe creasing when fully filled to 20+ lbs.
Your thoughts and suggestions,
Tia,
Don