The trend towards slicks or semi-slick tires on gravel
 

I've used a number of tires in the 700x32 to 700x45 size. I started using Vittoria Hyper touring tires on a Cyclocross bike ten years ago. The Hyper is a slick but always had enough traction on dry gravel for my usage. The easy rolling efficiency on pavement was an important benefit. The Hyper was one tire that was tough enough for gravel but performed like a road bike tire on pavement.

Once I moved to tubeless I tried a variety of "Gravel" tires including the Clement MSO, WTB Riddler along with a few others. These tires provided extra grip and safety in extreme situations, but clearly felt slower most of the time. I since have gone back to always using a near slick on the back of my gravel bike while using a tire with some shoulder knobs on the front in case I need to make an urgent maneuver on softer gravel or earth.

I'm noticing now that most bicycle tire manufacturers are offering a "Gravel" tire that is nearly slick in the center.

Will the trend towards nearly slick tires fit your requirements?

I mostly ride pavement, but it's also nice to have a more aggressive shoulder to air down and have some more grip in the loose stuff. So yes it fits my requirements.

:(The sandy dirt and gravel around here (San Diego) definitely challenges the grip of slick tires.

Depends on what you're doing the bulk of your riding on. Large cross section slicks are quite flexible, so long as conditions are dry.

Me, doing the bulk of my riding on bad paved-roads or packed and dry rails-trails semi-slicks work well....OTOH if I'm riding on pea-gravel, it calls for other tires.

The fastest, best all-around tire I've had were GKSKs that went bald after a few thousand miles. I hated to replace those.

If it was only possible to shave the tread down on some small-block knobby gravel tires to improve pavement performance without losing traction on gravel.

I run MSOs most of the time. They're tough, grippy in mud, easy to set up tubeless and offer a pretty good ride. They are definitely a bit slow-rolling compared to slick, though.

In the summer when the local gravel gets run in by farm vehicles and becomes smooth/hardpacked and dry I'll switch over to 100% slick Rene Herse Snoqualmies. My avg. speed goes up by 1-2 MPH typically when I do this and I don't feel any loss of grip on dry gravel. You also get the most insane hovercraft ride you've ever felt. Those tires are great if you can avoid flatting.

Someone could start a service to pre-wear-out the knobs. Like those jeans that come pre-faded.

Just run a file tread like the challenge gravel grinders or terreno zeros. MSOs and USHs are pretty fast on rough pavement too. I use GK slicks for an all around(mostly pave) and it grips well enough as long as I'm not on singletrack

Boy, my 40mm 120tpi tube Clement MSO tires feel as 'fast' as my Vittoria Hyper tires in 35mm. They are on different drop bar bikes(the Hyper on an old cannondale touring frame), but both bikes are similar weight and close setups.
Obviously an exact comparison isnt possible since they are on different bikes, but my point is that I just dont notice being slower on pavement with Hypers. Maybe I am the same speed and have to work harder to maintain that speed on the MSOs?

...or maybe this is more proof that I am not as refined as Barrett.

I'm in SoCal too--I'm running ByWays. Considering how they look they're pretty impressive on the loose over dry fire roads I ride--I was surprised when I first got them. But now 5-6 months in and I'm ready for a bit more tread.

I have to do water crossings. Slippery and loose rocks of a variety of sizes. I don't like them. I've assumed some tread helps so I use GKSK. They aren't really obnoxious on pavement but it would be interesting to try the bike with nice fat slicks.

Last night the post dropped off a pair of gravelking 700x38 slicks. I rode them to work and back. Really fast compared to my yksium xl 700x40 gravel tires . will put them on the trail this weekend

I have ridden smooth tires on gravel for several years. Compass is my brand (now Rene Herse). They have just about any width you would want and they are fast and very comfortable. Also ride Challenge Strada Bianca if I feel like I need something more durable...

Unless it is loomy, slicks are the greatest.

oh and aggressive shoulder tires are dangerous on pavement, when you roll the knobs. so for mixed riding give me full slicks.

the MSO 40 is pretty forgiving on rolling the knobs. but it will still cause a pretty good pucker.

Pavement plus hard pack gravel = slick style gravel tire. I have used aggressive designed tires and wore them out fast before 500 miles. This is a hard call since no tire can do it all so the best remedy is to switch out tires to suit the terrain. Yes a pain in arse but a necessary pain.

The GKSK's are very good on pavement. I recently did a couple (road) rides on new GKSK 38's..they really do feel much like a road tire...roll very easily. I run GK slicks on all my road bikes.

I have Hypers on my touring bike(35s that measure at 37mm). Wonderful tire on the road and dry rail-trail limestone. However, as soon as that limestone gives way to damp dirt..which in Wisconsin has a high clay content..it feels like riding on a skating rink.

Yes, the Hyper is not completely trustworthy on wet surfaces. Even wet pavement requires some moderation. I wouldn't recommend them to anyone needing a tire for gravel events. Not only do they become useless on wet earth, tubeless use is not possible and a tubeless tire has important benefits on rocky gravel roads. Like you said, they are excellent on dry crushed limestone rails to trails and pavement. The Hyper was one of the first tires in the 32-40mm range that could survive a day on gravel while being really fast on pavement.

However, several tires are now better in several important aspects.

If purchasing Rene Herse Snoqualmie Pass tires for a gravel bike that does basic Wisconsin pea gravel and some pavement, can anyone compare their experience with their Extralight vs Standard model? Is the difference in ride quality noticeable? Is the Extralight casing really fragile?

I fitted 38mm Hutchinson Overide tyres to my gravel bike back in January which when it comes to rolling resistance and speed, they have performed extremely well on road and well kept gravel, they are useless on anything damp though, they just sink and flick up dirt.

I really like these tyres but they have worn very quickly, these tyres have a very low profile diamond thread through the slick section but my rear tyre is almost completely smooth now, I'm going to switch the front with the back soon to get a little more life from them.

Given that I commute with my gravel bike every day and take some bridleways to work as part of my route, I couldn't imagine using anything other than a semi-slick profile on my bike. They are an excellent compromise between speed, comfort and grip.

A pure slick center will not meet my requirements, at least as my only tire. File tread maybe.

On pure finer gravel and hard pack a slick is fine. Not just any slick though, you need one that can provide comfort on that gravel. Gravel is not well defined either. If your "gravel" route has some washout, washboard with muck, deep areas, water, roots, areas with loose dirt etc, you can make it through but it gets sketchy. I did the GAP/C&O two years ago with Conti Speedride (file tread) and last year with Hutchinson Overides (slick center). The C&O is a mixed bag and can change drastically in one day with some rain or a recent flood. I will not use the Overide again for my trip this year, I made it and stayed upright last year but there were some close calls. With the Overide, my entire attention span was absorbed by looking ahead for potential hazards and deciding if I should go through or try to go around, eventually I stopped trying to go around things and just went through because they were unpredictable in that terrain, at least going straight I knew what I was going to get.. Sorry snake, it was you or me...

This year for my trip I will be trying the 45 Riddler. Coincidentally, my second ride with them was a century ride yesterday. About 50 miles of C&O and 50 miles of MUP/Asphalt. They were bliss on the C&O and fast with far better control (it was wet), I love the volume and feel. It's no MTB tire and peanut butter areas are still slick but it is predictable. Not as fast or solid as the Overide on asphalt and I won't be taking high speed corner with them on road but not bad either, they were noticeably better than the Nano I tried in the past on both surfaces.
I have two wheel sets because you'll never solve the perfect tire for everything problem. I have one with Overide 38 for road/off road and now one with the Riddler for offroad/road. For me, that is as close to perfect as I ever been. It really depends on your gravel and where you are riding to balance your desire of road vs mtb tire. If I was limited to one tire for all around.. the Speedride is it although there is zero chance setting it up tubeless so not for me.

I got maybe 3000 out of my rear tire and cords were starting to show. There is 4000 on the front and I have its replacement standing by. That high center section goes quick but the wear slows down after that.
That sucks for a +$50 tire for value but I like the tire so I'll deal with it. You could go with a touring tire but again... pros and cons.

It all depends on the gravel. I use Challenge Strada Biancas for my road / packed dirt / allroad tire. The 36mm Strada Bianca gives up very little speed on paved roads compared to 25mm Conti 4000S II's. And if I'm not racing, I figure it will let me work my way through any off-pavement surprises.

But for gravel races where I've never run the course? I'm not brave enough to take on an unknown gravel course with slick or slickish tires. This week and next -- on two very different courses I've never run -- I'm running Terrene Elwood 47's, just to be safe. For one of the two courses, I'm almost certain I would be faster on a 38mm tire that's slickish, but I won't risk it. I've heard the course includes some areas of bottomless talcum-powdery sand. For the other course, there will be multiple stream crossings, a route that runs in stream beds for a distance, and climbs/descents of over 20% grade. I wouldn't run a slickish tire there on a bet.

Unless I hit mud or otherwise slippery conditions, high volume slicks have always worked fine for me on unpaved roads.

I swapped out Smart Sam Plus's for Vittoria Hypers on my 29er last summer and they were great but lethal when it became wet.

I bought a gravel bike last November with GK SK's on it, saw some really heavily discounted Coni Speed rides and tried them in the winter but they were too slippery in the wet as well so swapped back to the GK's which were great in the winter and able to handle the mud where my friends were riding 29er's with knobbly's

As summer's on it's way I've just put the Hypers on the gravel bike and they're certainly better on the road, I've just put the Conti's on the 29er and there was a huge difference from Smart Sam's so will now just alternate between summer and winter tyres for both bikes but when my Smart Sams wear out I may get the wider GK's for my 29er for the winter.

One other tyre I'd like to try is the Specialised Crossroads, a friend stuck some on a Hybrid and when he did we were all really struggling to keep up with him on the paved sections, I'm not sure why these aren't more popular / you virtually never see them mentioned ...... although they are quite weighty which may be the reason.

Jan Heine wrote an article claiming that for gravel, slick tires had the same grip as tires with tread (which is why all their tires are slick except for one mud tire). He advocated adjusting width and tire pressure to maximize traction.



While in general I agree for dry conditions (that the traction can be the same), I will claim that there is a significant difference in breakaway characteristics. Slicks tend to let go fast, while treaded tires are easier to drift.

Of course when it is wet off pavement, tread can make a huge difference.