Tread type

[barnbeck]

I am going to do a gravel tour this summer.  Surface will be rocky to paved.  I will be riding 42mm tires equipped on a gravel bike.  What type of tread is best for this?

[John Nettles]

Honestly, it all depends on what you are looking for, must have, preferences, etc.  You also don't say what % of what type of road you are riding, i.e. 70% paved, 20% gravel roads (rocky???), and 10% dirt.  Also, what is the max width tire your frame can accept in the front/back.

That said, if you MUST have great traction off-pavement, then a somewhat aggressive type MTB tire is what you want but know that the paved traction and rolling resistance may suffer.

If you want an all-around tire used by many cyclists doing an epic "round the world" tour which typically encompasses paved to gravel to dirt and some limited rough rock roads, look at https://www.schwalbetires.com/bike_tires/road_tires/marathon_mondial  by Schwalbe Tires.  It is a pretty good jack of all trades, master of none tire with good durability and puncture resistance.  Be sure to buy from a reputable dealer as there are fakes out there.

I personally would use as wide a tire as your frame fits reasonably if doing much off-pavement roads.  With it, you can lower the air pressure and it will ride a lot better and grip better than a typical road tire without flatting near as easily. However, on paved roads, the a wider tire MAY slow you down, especially if not inflated properly.

Hope you have a great ride!

[John Nelson]

Every time someone mentions the Mondial, I feel compelled to remind everybody that there are two completely different tires named Schwalbe Marathon Mondial (the only commonality is their external appearance), so make sure that you get the one that has the characteristics you want.

[HikeBikeCook]

I have ridden Surly Extraterrestrials (26X46) https://surlybikes.com/parts/extraterrestrial on gravel and pavement and found them a good compromise. I am not recommending that tire in particular, (wanting a 26" tubeless limited my options) but I am recommending that style tread pattern. If you get a tire with a very aggressive tread pattern (Knobbies) it may give you great traction but, aside from rolling resistance, may be quite slippery on the road if the pavement is wet. Unless you are planning on all-out mountain biking (up hill climbing on a loose surface) you do not need a very aggressive tread pattern for gravel (IMHO) you need more "float" which comes from tire width.

[John Nettles]

Every time someone mentions the Mondial, I feel compelled to remind everybody that there are two completely different tires named Schwalbe Marathon Mondial (the only commonality is their external appearance), so make sure that you get the one that has the characteristics you want.

At least I didn't just say "Marathon"!  I really wish Schwalbe would use better names like just the Schwalbe Mondial DD for the Schwalbe Marathon Mondial HS428 with DoubleDefense. Sure they use could use just HS428 with DD but that is not as easy to remember as a mame, at least for me.  I just don't get why 1/2 the touring tires have Marathon in the name.  Must be a Netherlands thing  .

[ray b]

No tread needed for coarse gravel....
It's the fully loaded downhill into the 90 deg turn on an exposed dusty or muddy road bed that demands some knobs on the side wall.

Always fun.

I don't like the vibration of knobbies on pavement - so if the ride includes pavement, I run street tires including 42 mm slicks.

Remember, they call it adventure cycling....

[staehpj1]

No tread needed for coarse gravel....
It's the fully loaded downhill into the 90 deg turn on an exposed dusty or muddy road bed that demands some knobs on the side wall.

Always fun.

I don't like the vibration of knobbies on pavement - so if the ride includes pavement, I run street tires including 42 mm slicks.

Remember, they call it adventure cycling....

On the other side of that...
I have run tires with lots of low small knobs with good success on a mixed surface tour.  Mine were the Kenda Slant Six designed for MTB racing on hard packed surfaces.  They are also used for cyclocross in a different size.  I didn't notice any vibration and found the ride nice on all surfaces, but probably wouldn't choose them unless there was a significant dirt component to the ride.  I didn't notice it but suspect there may be some small increase in rolling resistance on paved surfaces.  As far as vibration and general ride comfort, I had no complaint the ride was silky smooth.

[BikePacker]

I am going to do a gravel tour this summer.  Surface will be rocky to paved.  I will be riding 42mm tires equipped on a gravel bike.  What type of tread is best for this?

I like my off-road treads to have a center bead so that when I am on pavement the ride, for me, is adequately smooth.

[froze]

It would be helpful if we knew you were going to be mostly on the road or mostly on rocks. 

I think tires to look at is the Schwalbe Marathon Mondial HS, or the Hutchinson Sector, or the Kenda Flintridge Pro, but maybe the best one is the Vittoria Terreno Dry.  Those tires lean towards gravel with some road use.  There are tires that lean more towards paved roads with some gravel use.