Moredepends on tires, 27 TPI vs. 60 TPI, vs. 120 TPI for instance. Finer thread tires will roll better at lower PSI than will coarser thread tires. Why? Energy lost to compressing a stiffer casing vs. a supple casing. Higher pressure and terrain feedback (You getting shaken to pieces by tungsten tires) gives an illusion of speed. FYI I emailed them on the weight of the new tires as compared to the old 26x4.0 and here's what they said. "The older 26 x 4.0" 120 TPI weighed 1250g. The newer and larger 26 x 4.2" 120 TPI black wall Van Helga weighs 1450g and the 26 x 4.2" 60 TPI tan wall weighs 1575g" MTB The reinforced XC racing tire for dry conditions + mixed terrain. Sidewall reinforcement, fast-rolling center tread, aggressive cornering, and an ultra-durable construction – this is the tire for XC trails that mix hardpack with root lattices, rocks, and puncture-causing trail debris. The 120-TPI nylon XC Trail TLR casing is durable The120 tpi will form to the ground better and be more supple, while the 60 tpi will be stiffer and more supportive. If you like to smash into berms at full speed then go go 60. If you ride more conservative and prefer comfort over aggressiveness, go 120. I myself have the 120 Recon+. No issues here. Alarge channel between the the center knobs and side knobs provides a looser, drifty feel desired by some riders. Single compound, dual compound, 3C MaxxTerra, 3C MaxxGrip, and Super Tacky options; 60 TPI, DoubleDown (2×120 TPI), or Downhill (2×60 TPI) casing options; Wide Trail (WT) sizes are optimized for 35mm inner width rims TheTPI count is fairly low, so they don't feel as supple as some of the tyres tested here with higher TPI counts. TPI (threads pre inch): 60. Bead: Wire. Weight: 370g. TPI (threads per Arelightweight 120 thread per inch (tpi) tires bad news for heavy riders? How about the midweight 60 tpi? Me: 270 lbs. Gear: 10 - 30lbs Use: Mountain trails, wooded off-trail, heavy gravel Are the 120tpi and 60 tpi durable enough? I want to be able to ride anywhere with little worry about the tires giving out, flatting easily, or catastrophic Itll tell you what you need to know. I know the diff between them, but there's also the difference in TPI 60 vs 120 that makes the comparison difficult. 60TPI (all else equal) is heavier and more puncture resistant than 120TPI and less pliable and slower rolling. That one is EXO. The 120TPI, (all else equal), is lighter less puncture cRST.