I use the Kenda or Q-Tubes Superlight 2.4" x 2.7" on my Fat bikes for weight savings. The regulars with schrader valves will be fine at 281g. Q-Tubes 26" x 2.4-2.75" SCHRADER Valve Tube

With that setback seat tube it's probably only good for flat pavement. I used to have a 7 spd Electra Crusier with similar design which was good for cruising around the coastal roads.