Branko D

Question - setting up a bike for roughly 50% road and 50% mostly light gravel (so, rarely there are patches of it which are really loose - most of it is generally firm with some gravel on top); stuff which is just rideable but fairly slowly and not fun at all on 23mm tires, is a 32mm road tire (such as a GP5000 TL) going to cut it, or would a thin-ish (33-36mm) gravel tire with a file thread and perhaps some side knobs help?

Is there much of a benefit to file thread over a slick? (Think Specialized Trigger Pro or Challenge Almanzo / Gravel Grinder) Does it hurt road handling, especially cornering with, granted, pretty small, side knobs on the road? I don't want something obnoxiously huge and heavy which is going to be slow or unwieldy on the road.

mstateglfr 

A lot of my riding is 50/50 paved and gravel, or 40/60 I guess. I ride paved to get to and come home from gravel. A 43mm tire is what I have because I am a hair slower on pavement with it, but its more comfortable on gravel. On a 30mi ride, I may get a bit tired of 32s on 15 miles worth of gravel roads.

My main road bike has 32mm tires and of course its totally capable of rolling over gravel, but I usually only ride a couple miles of gravel at a time in order to connect paved roads, so 5-10% of those routes on that bike will be gravel roads.

The Trigger Pro and Almanzo both have some pretty aggressive file tread in the center. For what you intend to do, I would look at a slick or something with a road file tread since that is really close to the same thing as a slick.
Gravel King slick 38mm, Gravel King SS 38mm, WTB Exposure 36mm, Rene Herse Bon John 35, Rene Herse Barlow 38 , etc.
I have experience with the first two on my road bikes and gravel bike, but not the WTB or RH.

Anything gravel oriented, even the fastest rolling larger gravel tires, will be slower than a tubeless 32mm Conti 5000.

pdlamb

Really hard to say without seeing your specific routes. I'll take my bike with 32s on some gravel and some dirt roads, but some roads really want bigger tires. (In some cases, with large, fresh "gravel" -- more like fresh railroad ballast -- much, much bigger tires!)

jonathanf2

I just ordered a pair of 32c GravelKing semi-slicks to add to my current 38c GK SK knobby, TLC slick and 40c WTB Nano tires. From test and reviews, the GK SS tires might be a good compromise for road feel and decent side traction. For example I feel I can take corners hard on rough terrain with the SKs, but with my GK slicks I can feel the rear loosing grip. I'm hoping the SS tires will meet somewhere in the middle in terms of handling, speed and control.

chaadster

Yeah, it’s so dependent on variables like terrain and tastes that it’s hard to say anything definitive, but I will say for my hardpack dirt roads on rolling terrain where I don’t have to transition between fast turns, running mid-width, file tread tires is a great compromise for mixed dirt/pavement use. I can’t stand the buzz of knobby tread on pavement, and can’t countenance the bouncy, mushy feel of low pressure, wide tires on pavement either, so Herse Bon Jon 35c have proven to be the sweet spot for me (to date) having tried 28c (GK slicks), 30c (Schwalbe S-One and Kenda Kwick K979), 36c (GK slick) and 47c (Herse Switchback) in that capacity. Weight is the other factor, too, and when the wights start pushing on 400g, I’m just not interested in pushing that much weight in circles when the weather is nice.

I haven’t tried them yet, but it looks to me that the GravelKing SS might be a great tire for my summer and fall riding. I’m planning to pick up a more substantial tire, maybe as big as 42c, this winter to see how the combo of volume and knob improves performance on hardpack snow dirt roads. The 30c S-One were pretty good at that, but I didn’t like their manners in the dry, and even the 28c GK slicks carried me fine for several winters of dirt road riding, though undoubtedly there’s a more capable and relaxing size and tread pattern for that. I’ll probably try Herse Steilacoom, Ultradynamico Rosé, or Schwalbe G-One Bite; it depends on how broke I am, so who knows what I’ll end up on!

I’ve not tried a totally smooth tire for dedicated gravel rides, but I’d guess that if it’s a big tire, riding hardpack dirt roads wouldn’t be significantly different than my experience on file treads. I don’t really see the point, though, as file treads don’t degrade the pavement experience and if they can provide a little extra measure of confidence on dirt roads, take it.

xseal

I have 2 sets of wheels, one with 40mm Maxxis Ramblers and one with 32 GP5000. If the gravel is very hard pack and/or is <10% of the ride, the Contis are fine. But any real gravel you need more.

rivers

I have 2 sets of wheels for my gravel bike- one for road (commuting and winter club runs) and gravel. The road wheels have 32mm Pirelli Cinturato Velos. They are fine for gravel you would find on a tow path. They will handle a bit of single-track if dry and it's not too rocky. I think Pirelli developed them for races like the Strade Bianchi. Anything more than that, I'm using my gravel wheels (which have 40mm Hutchinson Touregs on them).

tyrion

You definitely feel those side knobs when you lay it down in a corner on pavement. It feels a little unnerving, and I never corner as hard with a gravel tire on pavement than I do with a slicker tire.

Happy medium for me is Gravelking SS.

msu2001la

I ride 32mm tubeless GP5000 on hardpacked dry dirt and "light" gravel trails (think crushed limestone) all the time. It's great.

I've never found much advantage to file treads. I've tried them for early season dry CX racing and always found the cornering traction to be weird, and the filed down center doesn't really seem like it rolls any faster than a normal tread. I do like tires like Challenge Baby Limus, which is a slightly filed down version of the regular Limus, but something like a Chicane? I don't get it.

dwmckee

Yes, the GK Slicks have something about them (harder compound?) that makes them quite "slick" on paved surfaces and we do not recommend them.
I do not ride anyting below 35 MM even for all pavement riding and I suggest that you go to at least 35 MM for a better ride on both pavement and gravel. The Rene Herse 35MM Bon Jon Pass (file tread) is an excellent tire that if fasy and comfortable on both.

jonathanf2

I just did a group ride tonight with the GK slicks, and on a fast downhill descent my rear was definitely slipping. In fact it made for a pretty scary downhill considering their was several dozen riders behind me! In fact I think I'm faster with the GK SKs because I can bomb the downhill on the curves knowing the tires just stick even on loose gravel and soft dirt.

I definitely like the cushiness of 38c and above tires, but I just felt like trying something different with the 32c tires I ordered. I just checked out the Bon Jon Pass tires and they look pretty good, maybe I'll pick up a pair down the road.

Fentuz

Last summer, i run 35c kojak slick on gravel and occasional pebbles - admittedly it was on 20” (35-406) and it was fin at 45psi. I even rode on new year day on muddy single track without issue.
so in summer-ish condition, a 35 slick should be fine especially if you are road biased

Badger6

I've used both of those tires, and both roll fast enough on paved surfaces, and performed very well on gravel. But also, have you considered the Roubaix Pro 30/32? At $40 a tire it is a smoking bargain. It works great on any surface that you'd want to put a file tread on. It is supple, has great grip, and wears forever. And, frankly, for the perceived decrease in effort required on pavement (and longer wearing on pavement), there wasn't a similar loss in performance on gravel. That said, the gravel I am referring to is the type that consisted of crushed stone over a well compacted dirt base. None of the tires performed well in mud.

Badger6

msu2001la the Chicane/Almanzo/Gravel Grinder tread is excellent when the crushed stone surface is loose, or in "light" sandy conditions. Agree the cornering can be strange initially.

mstateglfr 

To clarify, are you saying the 32mm GK Slick is sketchy on unpaved surfaces or on paved surfaces?

Dino_Sore

I've used the 32mm Panaracer GravelKing Plus slick for mixed surface rides. It does a pretty good job on the road and can handle some pretty rough off-road surfaces, so long as it isn't big chunky stuff or deep sand (where you need more volume). I have a tendency to explore, and usually end up on roads and trails totally unsuitable for a 32mm tire, and I've been surprised by how the GK slick held up. Is it as fast as a GP5000 TL on the road? I don't know but I doubt it. Panaracer also make a "non-Plus" version that may be a bit faster on the road, but a little less durable off road.

I've seen people say the GP 5000TL is perfectly suitable for the 50/50 riding you describe. Personally, I'd be a bit leery of using a road tire for 50% dirt, even if it is well groomed. But, I have no experience with the GP5000 TL - maybe others can chime in. I would lean toward sacrificing some road speed for off-road durability.

Branko D

Thanks for all the input, really appreciate it!

In a fit of indecision, I ordered both, but I'll fit the Almanzos first and see how they handle on road and offroad.

jonathanf2

My 38c (not 32c) GK slicks are sketchy on fast hill descents with lots of curves on both paved and unpaved surfaces. Last night on a group ride being a few feet from other riders, I really needed to pay attention to my braking. I still like them mainly for straight solo road riding, because they feel fast and I can easily go over the terrible roads here in LA absorbing most bumps.

On the other hand, my 38c GK SK knobbies are a bit more sluggish on the flats, but I can go much faster on down hill roads with loose dirt and gravel, the grip is vastly better taking the corners with none of the slip.

chas58

I have 2 sets of wheels, one with 40mm Maxxis Ramblers and one with 32 GP5000
For me, it really comes down to tire pressure. the 32s are often at 50 PSI, and if I'm comfortable with that and I'm not gonna bottom out, that is what I will ride. In the late summer/early fall our gravel is smoother than our asphalt, so this works great for me.

If I need lower pressure or ability to ride rougher stuff I'll go with the ramblers. But for 50/50 mixed riding - its usually the 32mm tires (if I'm not on rough or soft stuff).

chas58

These comments always puzzle me. Do you guys really need knobs? Maybe I've been mountain biking for too many decades and take technique for granted. But slicks are fine for gravel. Bicycle quarterly did a nice article on this:
https://www.renehersecycles.com/myth...r-on-the-road/

I'm gonna think that if you are sliding around on slick tires, your technique and tire pressure isn't right.

But, to counter argue Jan - I'll say that the breakaway characteristics of slicks are much more abrupt than treaded tires. This mostly makes a difference riding off road in wet conditions. In the dry, its hard to pick out.

jonathanf2

I'm riding between 35-40 psi in the rear, should I go down to 30 psi? I don't think I'd feel comfortable riding these tires at higher pressures.

xseal

On gravel you need knobs, eg, to brake. I just did the SBT gravel race in CO. Going 35mph on gravel roads that are loose on slicks would have been unsafe/unwise; eg, there would have been no way to slow down to make one of the many 90 degree turns (which probably could have been taken at 35 mph on knobby mtb tires). And I road raced motorcycles for many years, there's a reason rain tires have huge grooves/knobs and dry tires are slicks, technique has nothing to do with it. Any pro DH mtb racers using tires w/out knobs? no. Gravel isn't a DH track, but it's somewhere in b/t that and smooth asphalt, meaning the tread should probably be somewhere in b/t that you'd use on a DH mtb and a road bike.

veloz

Before gravel tires existed, many folks used Paselas as they come in widths up to 37 (I think). Just enough tread to cover fair weather gravel and not too slow on pavement stretches. I've raced on 32's and 35's. They hold up well for gravel and off road tours too.

chaadster

It seems a GravelKing Slick handling issues hysteria has gripped the Gravel forum.

chas58

Curious then, as to what you thought about Jan Heine's article I linked above?