I got in 3-days of riding the Fatback Titan in my local backyard (Blue Mtns) this past week. Each day I was presented with differing weather and snow conditions so every ride turned into a tire analyzing experiment. Oh yeah! My super analytical mind has been wondering again (actually it never stops) so the "real-life" analysis lab has come to life once again.
On the first ride I was testing some new Fatback Sterling tires that I received recently. On the first day using these tires the snow was rather deep and almost wet which would challenge any bike tire. I had a very fun day of "testing" but realized quickly that the Sterling was not an optimal front tire in these conditions. It simply did not have enough volume to allow the tire to float well in this type of snow. Evidently the Sterling width is less than Fatback spec'd with Vee Rubber (who manufactures the tire) and Fatback is working on a solution as I understand from their blog. Overall the Sterling is 3.8-inches on my rims, which wider than the 45NRTH Husker Du tires, so I'm not dissatisfied, but I would like a tire that is 4.2-inches as advertised. I will patiently wait to see what Fatback does to correct this (evidently their proto types were 4.25 inches on rims similar to mine). Anyway, I was able to test the traction on the front as well in both directions and found the tread pattern seemed better in the opposite to their directional arrow on the front. As a rear tire the traction was quite good, second only to the Surly Nate in my small arsenal of tires (Surly Larry, 45NRTH Husker Du, and Surly Nate).
The 2nd day the snow was much wetter and temps warmer plus it was raining, so just imagine really wet snow. Some people would think this would be pure misery to ride in, but I had a blast! Thinking that I would need more even float and traction in these conditions, I put on a Surly Bud up front and Surly Nate on the rear. A huge improvement was noted with floatation (the Bud is 4.5 inches wide whereas the Sterling nearly an inch less width). Also I felt I had better rear traction with this setup (the Nate is hailed as the best rear tire for traction by many more people out there than me). I still had issues sinking through the crust and the snow, however I really do not think any tire combo would have done much better in a steady rain making wet-soggy snow that was hard to pedal through - fun right?! (old photo showing this tire combo)
The final day I put on the 45NRTH Husker Du tires front and rear. The weather had cooled after the rain making a nice crust of the previous day's rain-on-snow event. I was popping through the crust now and then, but for the most part it was easy riding on top of the snow. There were also huge ice patches in which only a studded snow tire would have conquered without slipping. I learned that the Husker Du was really not a good rear traction tire even in these ideal conditions. Some people would dispute this with me, but climbing a 1000-feet in the first 2-miles of my ride tells me exactly how good or bad the traction is for any tire. I'm not at all impressed with the 45NRTH tire in the rear. Up front it is a great tire on firm snow. I've used this tire several times in the past in various snow conditions and had similar results. Considering their low volume and lack of traction compared to the Sterlings and Surly combo, I am considering selling the 45NRTH tires. (another old photo - by-the-way, this bike is for sale)
One thing is certain - Riding a fatbike on groomed or well packed trails is fast and easy, but riding a fatbike thorough deep snow is one heck of a workout and incredible interval training. Wet deep snow is real training (not that I'm training) in both the realms of physical and mental toughness. All I can say is that if fatbike season came before cyclocross season, I'd be ready for some serious racing.