As long as cycling has been a sport, riders have always sought out the edge they need to push harder, ride faster, and finish sooner. In the past, this meant getting the thinnest tires possible, which makes sense. The lower the rolling resistance, the faster and more efficient the bike, the faster the rider will finish the race. Don't you think? New developments in bike technology have shown that tires that give the rider a little more cushion and traction and, depending on the discipline, the ability to ride through loose and unstable conditions, will lead to a faster commute time.
It's all about the traction
A wider tire has the advantage of having more rubber on the ground, allowing the rider to accelerate faster into corners and brake later. For the average rider, this means wider tires will give them greater confidence when turning and confidence knowing their bikes can be stopped when needed.
The trend has been most apparent in mountain biking. It's all about traction when it comes to downhill mountain biking, from full suspension bikes designed to keep your wheels on the ground as much as possible to big knobby tires that keep your bike from sliding out from under you. From the 1.95-inch tires of the 90s, mountain bike tires now reach a width of 3 inches. This has led to riders taking turns faster and even braking later because they know that with so much more rubber on the ground, they can stop at any time. Whether it's descending gravel roads around Seattle or navigating frozen roads in the Midwest, the 4-inch tires will keep the bike stable regardless of the conditions.
Suspension with air-ride
The additional cushion that larger tires provide is one of my favorite features. To ride safely, the lower the tire pressure you need, the larger the tire volume. When the air pressure is lower, bumps in the road are better absorbed and the ride is smoother. As a result, on ebikes, where efficiency is even less of a concern than on traditional bikes, going from 2-inch to 4-inch tires dramatically reduces the impact of rough roads.
Compare this to your regular commuter bike. About twice a week, I commute on my road bike, which has a "generous" 1.25-inch tire with 95-105 psi. Although my road bike is extremely efficient and zippy, my tailbone definitely appreciates the cushion the ebike provides.