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!
Fantastic overall cross race tire. I actually prefer these to the higher end Challenge tires. They're easier to mount and more durable. Plus they are designed for a slightly narrowed internal rim width, so when placed on internal rim widths of 20mm+ they plump out to be around 35mm wide - which is a little more comfortable and I think is perfect for my local CX scene.
4 stars because the sidewalls on all the Grifo's I've ever purchased seem to be a little thin and tend to leak a little sealant through the CX season. Not a big deal, but it does mean you need to top off a little more often than other Challenge tires.
I just used these for a 240 mile gravel race with all the types of (dry) gravel. I had to slow down a lot to safely take turns, but it was worth it for the low rolling resistance on the straightaways. They're also nice and fast on the road, though slippery on wet pavement. I will be keeping them around for long rides in dry weather. I would not recommend them for races that require fast turns. If I could have these tires with side knobs for turning, they would be perfect.
Installation was difficult the first time due to the wire bead, but it was reasonable with two people and two tire levers. Subsequent removal and remounting was very easy.
