Gravel grinding or whatever term you want to call it is the hot new thing in road cycling. But because the bike industry is rushing headlong trying to capture as much of this “new” market share and the dollars that go along with it, there are a ton of products being thrown out to you, the consumers with the “gravel grinding” moniker attached. Many of those items look wildly different from each other and you’d wonder how something designed for a specific use could vary in size, construction, appearance, and price so much. Tell someone they need a tire for their road bike and they pretty much have a good idea of generally what it is. Same with a mountain bike tire. But what do you think of when you want a tire for this hot new trend sweeping the nation? Best answer? That depends. But stick with me and I’ll try and see if I can shed a little light on the matter so you can walk in armed with the proper knowledge to be able to plunk down on a new set of treads.
First things first. There are all types of gravel and terrain that make up the genre “gravel grinding”. (Anyone else getting tired of that term yet? Sorry, it’s the best I have so far, so you’ll have to keep hearing it for a while until something better comes along. I’ll try to use it sparingly.) The types of gravel you’ll encounter will be dictated by the terrain you live in, the budget of your county, state, and federal road managers, what the roads are used for, and just what types of surfaces you personally are willing to travel down. For example, in the midwest, there are tons of rolling gravel roads that connect the small counties and farms of the area. Out here in the PNW, many of our roads are there because of the logging industry and they tend to go winding up into the mountains and back down. Sometimes the roads are irrigation canal accesses or abandoned sections of highway that nature has reclaimed when the straightened out and widened the roads. Also, a lot of the bikes and tires out there work pretty darn well on less severe trails and singletrack. And in case you didn’t notice, but even the quality of the asphalt the highway crews are laying down has gone down in recent years. Hell, half the time it isn’t even asphalt, it’s chip seal and the size of the rocks they use keep getting bigger and bigger to save money. One last thing, even if you only ride on the road and never venture down the beaten path so to speak, if you ride anytime between November 1st and May 1st and live in N. America you may have picked up on that the shoulders you occupy are filled full of sand, cinders, glass, and de-icer essentially making every road ride a ghetto gravel grind by default.
So long story longer, when it comes to deciding what type of tire to choose it pretty much comes down to the types of gravel, dirt, trail, and pavement you’re going to be on and how much of your overall riding you’ll spend on each type. If you spend the vast majority of your rides on pavement, crappy chip seal roads that at worse look like this:
then I would stick with a basic road style tire. But pick one that is bigger than a 23c and has some sort of puncture protection. 25′s are nice and 28′s are even better. You don’t really need much in the way of knobs or even tread, but having a higher volume tire to smooth out the small pebbles, rocks and occasional washboard is much nicer. You won’t feel like you’re getting bounced around and your comfort and control will go way up. Basically you’re putting on your own Paris Roubaix tire. Sure that race has sections of cobbles, but they only make up about 90k of the 260+k that is that race. Just don’t forget to air down. There’s no reason to be running 100+ psi in a 28c road tire. Think more along the lines of 70-80psi and you’ll really like the smoothness and control of the ride.
*Just a quick aside. Service Course Velo has been using and carrying Clement tires for the last two years and I can’t say enough good things about them. So throughout this article there are going to be times where it’s gonna to sound a bit like a sales pitch. That’s because it is. I’m just giving you fair warning.*
The Strada LLG is going to be your weapon of choice for these types of rides. It comes in three sizes (23, 25, and 28c), two sidewall color options (tan or black), two casing thread counts (60 or 120tpi) and tow rubber compounds (single or dual). The 60tpi tires have the single rubber compound and you have the option of black or tan sidewalls. The 120tpi tires are just like Henry Ford intended (black only). Both have a puncture protection strip running under the tread, but the 120tpi tires have puncture protection running from bead to bead.
So lets say you have a bit more gravel in your regular ride diet, but there’s still a fair amount of pavement you do daily. You take the bike down the occasional trail, but nothing too crazy. You need a tire that does it all pretty well and transitions from one surface to another without making too many sacrifices along the way. When you do venture off the pavement, the rocks and gravel is starting to get a bit looser and rougher too. Check out the USH.
At a 35c, it’s going to be too big for your road bike, but that’s fine because you won’t be taking this tire places you’d really want to take your road bike anyway. See that center section? It’s raised, smooth and has an inverted tread design. That means it rolls smooth and fast and offers more puncture protection. The side knobs are designed to let you lean the bike over on pavement without a big side lug that will squirm and wiggle. It really initiates high speed road corners much like a road bike tire. As you go outward on the tread, the side knobs get larger and more open to help grab in the loose stuff. This is the tire that both the Cyclocross World and Raleigh teams put on their bikes for training, and commuting back and forth to the race venues. 7 out of the top 10 finishers in the Dirty Kanza gravel race were on this tire.
Lets say the gravel you like to seek out is a bit looser, a bit bigger, a bit steeper, has more singletrack peppered throughout, and while there’s less overall pavement, you still need something that doesn’t buzz down the road like a tractor tire and lets you keep up with the roadies you encounter. Meet the MSO
The biggest difference is that the casing size bumps up to a 40c. This is the tire you use when the gravel is going to be the predominant surface and is rougher and looser. It’s tread blocks more open to help the tire grab in loose and uneven terrain. The side lugs are now looking pretty beefy to help grab traction when leaned over on the trails and rough stuff. The center section is still very smooth rolling and fast, but it’s still more open to help it grab traction when climbing and descending steeper and looser grades. This tire is almost a mountain bike tire, just downsized and civilized a bit to be more versatile and longer wearing.
Not all bikes will fit a full 40c tire though. If that’s the case Clement makes the MSO in a 32c size as well. It’s not going to have the flotation in the really chunky stuff, but it rides very simirly to it’s big brother. If you are the whipper racer type looking for a lighter version of the 40c MSO, the 32c is your ticket.
Here’s a pic of all three tires side by side. 35c USH, 32c MSO, and 40c MSO. All three tires come in 60tpi with a single rubber compound or 120tpi with a dual compound.
Another side note. People often ask why buy a gravel specific tire like one of the X’Plor series form Clement when I could just use a cyclocross file tread? File treads work pretty well actually. They roll fast, have decent volume, and even side lugs to help up when the gravel get loose. They have a couple of downsides though. One is that because they are designed to roll fast on hard pack and grass cross courses while still cornering decently, they often have a more square profile. That works great when leaned over in a grassy corner, but not so well when turning on pavement. Those chunky side lugs start buzzing a squirming pretty quick. The other issue they have and it’s actually the worse of the two is that they wear quickly. There isn’t much rubber on top of what is essentially a bald tire to begin with. Not only do you have to replace tires more frequently, but you risk of flatting and cutting the casing get pretty high pretty quick. Check out this picture of a Clement LAS semi-slick on Ben Berden’s bike after only 400 miles.
Feel free to swing by and pick my brain abut gravel tires. And while Service Course Velo stocks, sells , and rides Clement tires, there are other brands and models out there so please don’t hesitate to ask about them.