Challenge

I bought a set of these in the 45mm tan wall spec. These tires are definitely hard to mount, and if you're wondering why, it's because they are flat like a lasagna noodle due to the manufacturing process. The tire wants to lay flat, rather than arch up and press the bead into the wheel itself. Soapy water will help, and you may want to consider letting the tires sit in the sun for a bit to soften up.

Now that the tires are on, they have held sealant and air exceptionally well.

I've run them for about 200 miles on a mixture of gravel surfaces, pavement, and even a little of what we call Class IV/VI roads in the NH/VT area. The bike is a Cannondale SuperSix Evo CX/SE. With a total system weight of about 180lbs/82kg, I've been playing with pressures between low 20psi and low 30psi. The lower pressure offers quite a lot of comfort and grip without feeling sluggish or unresponsive. The higher pressure honestly doesn't feel like it's worth the trade on comfort and grip, but it is probably technically faster. Somewhere in the middle is likely best for me and my weight. I haven't run these in the wet yet at all, so I can't speak to that performance. I probably won't, since this is my fair weather speedy bike.

Would buy these again without hesitation, unless I just wanted to try something else.

There is no better way to celebrate the end of summer. Removing the old dried out tubulars, scraping away (most) of the old glue, and breaking out the acid brushes to apply a fresh layer of smelly contact cement is the perfect way to usher in the grey skies and early nights. The Grifo is the go-to for all but the sloppiest days. A file tread could be faster on a dry day, but the added traction of the Grifo helps with confidence when you're trying to out corner that skinny faster-than-he-should-be masters rider.

Don't expect these to last for years. If you stay off the pavement the tread will stay sharp and grippy, but the tread may peel off the casing after a season of use. Still, love riding these.

Picked these up on sale to try since I love their CX tire lineup and the ride quality of their tires, both handmade and vulcanized lineups. Wanted something for grippy for single-track and chunky gravel that still rolled adequately fast on the smooth stuff. These tires are very similar in tread as the CX Grifo tire they make, with the center knobs being the exact same.

Now my assessment, these things absolutely blew away my expectations. Have put them through their paces from fast XC style single-track with some rocky technical terrain to smooth road and gravel. Had a blast keeping up with our fast XC MTB group on my Niner RLT 9 gravel bike. They run well on the smooth gravel with just slightly more rolling resistance than the Pirelli Cinturato Gravel H I run for the smoother stuff, but cornering confidence and chunky washboard, these really do behave way better, something to be said about Challenge's Handmade casings I guess.

The only real downside is the mounting process. If you're not familiar with mounting handmade Challenge tires, well, they can be a real Challenge (pun intended). It's worth it in the end though. These are definitely great tires and will be my go to all around mix-terrain that leans more into trail and single-track for sure!

These are clearly a top tier tire and they score well at brr.com. Though, the rumors are true, they are a Challenge to mount. I've changed a lot of tires in my day and I'm a machinist so I have a "mondo set of tools". I set these on American Classic Hurricane alloy wheels. Doing this without inventing new cusswords or throwing things across the garage required: a stout pair of irons, a pair of small clamps to act as stops, Schwalbe tire lubricant, and no way were they going to seat without an air compressor. Prior experience with cantankerous tires helped a lot. Worth it? I think so!