Back in the spring, I put a G-one R pro up front and an RS on the rear, and have put them through quite a bit of gravel riding and racing.
The 50s barely fit in the frame and fork and have rubbed down some of the protective tape I put in the chainstays. But it will be hard to get me to go back to a smaller tire. I've crept the pressures down a touch, sometimes to 21/23 f/r, and even the RS semi slick has pretty acceptable grip when you have that much volume and that low of pressure. I raced on these at Get lost gravel in hamilton and got another 2nd place. My whole year has been about almost but not quite winning it seems. The tires were great all day though. Mostly I just screwed up at the end.
The rear tire did wear out sort of quickly, and the insides of the edge knobs are pretty much all shredded off. Next I'm going to try the R pattern front and rear. The R will have a bit more grip and maybe better puncture protection with the small, tightly spaced tread blocks, but in testing is only barely slower than the RS on a drum. I definitely rode the rear tire much longer than I would have liked but there was pretty poor tire availability all summer.
I have still been riding it, haven't gotten any punctures since that one, and even on trails and steep gravel descents the grip is like, still fine. That's kind of the thing about a higher volume tire- you don't need as much tread.
So yeah, I think the g-one pros have been about my favorite all around gravel tires and they're conveniently about the fastest thing out there. Big handmade challenge tires get the edge for having the smoothest ride feel, and the pirelli gravel RCs had better cornering grip and feel. Mainly though, bigger tires are better. For a bike that gets ridden off pavement, it's hard to say why you would ever want a tire smaller than what fits in the frame. Mud clearance for cyclocross? Probably I will have to go back to something different/smaller especially with my new wider wheels. I really need the tires to actually measure 48-49mm instead of 50-51. The 45 challenge getaways were just about perfect in that regard and pirellis also measure on the large side.
