I purchased these after experiencing reliability issues with another tire. I found myself riding hard-core gravel and wanted a tire that could withstand the punishment, but still provide good rolling resistance on pavement. For me, it was between these and the MSOs. I ran the Gravel Grinder Race for 8 months with acceptable results.
A few notes Tubeless performance was unsatisfactory. This was disappointing, but they were not sold as tubeless ready, so what can you do? This is the main reason I don't run these anymore, and why i gave only 4 stars. Another observation is those larger side knobbies. To me, they seemed like a distraction. I did not like the way they felt underneath when they engaged. It felt like the tire changed its characteristics whenever in a hard cornering situation (which is where I want it to be the most consistent). Get rid of the side knobbies, they're dumb.
The tire looks good, rolls well, and is reasonably tough. It's a good alternative to Clement MSO or even USH. Do not expect to run these tubeless. I found they wore a little faster than I'd hoped for.
I set these up tubeless with Stan's no-tube cyclocross kit on standard rims (Mavic Front, Powertap alloy rear), and have been playing with various pressures between 20 and 40 psi. Have done one long race (107 miles) in Minnesota, and lots of training. Will be riding this in the Chino Grinder (Arizona) this weekend, the AlmonzoRoyal 162 next week, and the DK in June. Hoping the lower pressure will allow all of these to run a bit better than with tubes and higher pressure. So far so good. I'll update if I have any problems.
I use my Specialized Crux as a cross-gravel-secondary road training bike and put a lot of miles on the bike. I wanted a good gravel tire that would be able to handle a wide range of terrain and still roll well on the road. This tire has been the perfect tire. No problems with punctures, easy to run low pressures for rough roads, good traction, and rolls well on pavement. The width is very nice and the key to this tire. On 25mm rims the tire measures around 40mm and that is key in its ability to maintain traction on really rough gravel roads. The side knobs are nice when you corner as you start to slip and then they kick in and you get the much needed traction. I have not used this tire tubeless.
I trained on these for several months and several thousand miles - mostly on pavement - leading to this year's Dirty Kanza 200. Then, I mounted a new set for the race itself. On pavement, these tires run fast. I did group rides on pavement with my roadie friends and stayed in the lead group. No problems. In fact, I still hold an 8-mile paved Strava KOM with these tires and couldn't beat it last weekend on my 25mm road tires on my road bike. In the Dirty Kanza 200, I think these are the perfect tire. Excellent in all conditions, including loose gravel, big gravel, sandy dirt, and the rough, rocky descents of DK. Very stable. Excellent traction. Always lively. And NO FLATS! I weigh 170 and I used 5055 inflation pressures.
Many people rave about this product but I had a disappointing experience. One of my tires had a bulge that was big enough to be noticeable from bike-mechanics' eyes, and annoying when riding on a paved road. Otherwise, they felt like a great choice for gravels with a very supple feeling and a good balance of low rolling resistance and traction (but I only rode 60miles with them). Thankfully, the customer service at BikeTriesDirect.com provided me with Clement MSOs as replacement (because these were already sold out) right away. I am very happy with MSO. If you choose these tires over MSO (and I can see there are a few reasons to do so - slightly narrower profile (better tire clearance), lighter weight, familiar tread patterns (for CX cyclists), etc, I would make sure the tires are perfectly round before riding.
Put 400 miles of gravel under them so far and no flats. They are fast rolling and corner well with the large side knobs. Surprising grip while climbing on gravel. The sidewalls are supple and the tires feel great at the recommended 45psi
These are the best tires I've found for riding gravel and dirt roads. They have a tall/narrow profile so they take a lot of the edge off the roads but still roll pretty fast. I can feel the weight when climbing but otherwise don't feel much slower on these than I do on my road bike running 23's. Not good in mud, but good enough on dry singletrack as well.
They do wear somewhat quickly on pavement, rotated after about 500 miles. But I haven't found a tire with any kind of tread that doesn't.
Used these tires with Challenge latex tubes for two 62 mile gravel races, Barry Roubaix and Rough Road 100. Inflated them to 45. Very comfortable ride. They roll super fast on all surfaces. While others were flatting over a particularly rough section I was fine. These are my go to race tire. Of note, the rear tire is wearing very fast. I have done some, not a ton, training miles on the road but am still a little surprised how fast the center tread is wearing. I have a set of the Clement LAS tires that have way more road miles and show little signs of wear. Lastly, while advertised at 38 I'm not sure they measure out that wide and I'm using the Industry Nine i25 wheelset which has a bit rider rim.
I'd been running Sammy Slicks as my summer tyres, riding a combination of gravel roads, fire trail and single track. Bike is a Lynskey CX with CurveHope wheels. Having read a review or two on the Grinders, I pulled the trigger.
They are better than what I expected, so much so the Sammy's are gather dust on a shelf. The width, volume of the 38mm makes a noticeable difference in handling. As the seasons progress the track and road surfaces dry out, and turn from hard pack to loose gravel and sand. I run 5560 in the hard pack, and 5055 once the gravel starts to break up.
Tyre wear wise, the rear is holding up well, more so compared with the Sammy's. Comfort and performance wise, they are probably the best tyres I've ever ridden. Some of the routes I ride include a return on tar seal roads, and on those I can happily sit on 27-30kmh as a warm down.
I've not tried the lightweight inner tubes Challenge recommends, I'd prefer a tubeless, but will have to wait.
Bought this tire to ride on gravel, obviously. I'd been running Challenge Eroicas, which ae nice, but still a little squirrelly in deep gravel and fast down hills. These though, are the cat's meow. Rode the Oregon Stampede on them with no flats over 125 miles of jeep trails, basalt gravel, large rocks, and pavement. Had no body soreness afterwards either, which attests to their incredbly flexible sidewalls and shock absorption. Have put around 500 miles on them total, and the tread still looks new. Plush ride, tough, runs equally well with 75 psi or 40 psi, what's not to like.
I have ridden hundreds of miles on pavement, gravel and dirt roads. The center tread allows less rolling resistance on pavement and outside knobs provide cornering grip on looser surfaces.
These tires work well for pavement, gravel and dirt. They have minimal tread on the center and are lightweight for low rolling resistance and the knobs on the sides provide traction in looser terrain.
I've ridden these for 2 seasons and, overall, I like them. They roll fast on pavement and dirt, they wear well (still plenty of life left on mine - I rotate FR each season), I have yet to get a flat, and they're a good value on sale thru BTD. My one con is that they bite hard in corners, especially in loose gravel and dirt. My go-to loop is a mixture of pavement, graveldirt roads and some fast stretches of singletrack. I find that when I take a loose corner at speed, these will start to slide at first and then bite hard as the outer lugs grip. For that reason, I'd say they're best suited to dirtgravel roads (as the name implies) than high-speed singletrack. It's not a deal-breaker for me, but you do need good bike handling skills so as not to over-correct.
I've only got one ride on these but I'm super happy with them! My clement tires aren't very confident cornering, even on the road. These challenge tires transition real well in corners and lock up nicely on gravel. Reasonably fast on road or dry hardpack as well. Corner well in gravel.
I mounted them on a pretty narrow pair of road rims (vuelta) and my micrometer says they're more like 32's on these rims.
