Originally Posted by
unterhausen
I was pretty happy the year I rode all my brevets on 38mm tires. And those tires are relatively crummy, not RH quality. I don't have that much experience with knobby tires, but a lot of them have a tread pattern that rolls fairly well on the road. There is a lot of riding on relatively smooth roads in mountain biking too. The downside to fat tires is weight, if acceleration matters at all. But generally it doesn't.
Fat tires are a no-brainer for gravel, they are definitely faster than narrow tires, even disregarding the lower likelihood of flats. That's not inconsequential around here, the gravel roads are built with a base layer of really sharp rocks somewhere between softball and football size. There are inevitably some of those rocks poking up through the top layer, and bikes are attracted to them like a supermagnet. I use gravelking small knob for gravel. They are a bit more robust than slicks, but they still roll really well on pavement.
Sorry if I'm detouring the thread a bit, but I recently put some gravel king slicks on my Diverge. Went with 32mm for comfort and wanting a little wider tire for a race this June that will include some limestone trails and gravel (only about 6% of the ride). Really liked how they rolled, but a few weeks ago hit some loose rock while riding on chip seal in the Texas Hill Country and slide on my arm/leg/shoulder/hand. I'm wondering if I made the wrong tire choice. May have lost control if I was using my regular tire (Armadillo all-purpose), but it is obvious to me that the slicks are not as stable on the road. Maybe the small knob? Your thoughts.