Touring - Tires for touring on gravel

I'm planning a trip this summer which includes more than 700 kilometres on gravel or loose surface roads. I'm planning to swap out the 700x32 tires on my bike with something closer to 700x37 to 700x40. What do you suggest?

No tire is perfect for all conditions. IMHO, you'll need a tire that can handle what you'd rather not walk. If the worse that you'll always be riding on is gravel and you're only talking 700 km, I'd go with the Marathon Extreme: if there's also lots of asphalt, I'd go with the Marathon Dureme. I'd go with the 700x40 if I could still fit fenders, but 700x35 if I couldn't. OTOH, your 700x32 isn't that much skinnier, so...

If you act right now, you can get at Amazon the go-to touring tire for gravel, the discontinued Marathon XR in 700x35. I get 7500 miles with at most 1-2 flats. I got 3500 miles with lots of flats with the Marathon Supreme, the slick version of the Extreme / Dureme.

If your bike will take a 700 x 40 I would go with the Marathon Extreme. I have toured with the 26 x 2 version, both on pavement and gravel and I love the tire. It rolls remarkably well on paved roads but gives great traction on the rough stuff.

I have done 1800 kms through Mexico on mine and just did some crazy sand roads on them this weekend.

Enjoy your trip.

I decided after a tour on gravel that my 700cX37 tires were too narrow, a friend had a mountain bike with 26X2.0 tires and his tires rolled over the thin veneer of loose gravel overlying the hardpack much better than my tires. Mine dug in and his rolled over the gravel. Since then I built up another touring bike with 26X2.0 tires and am quite happy with it for off-of-pavement trips while the 700c bike is my on-pavement bike.

That said, for only 700km, the 37mm width (or wider) should be adequate as that is not very many days. I tried wider than 37mm on my 700c bike and had fender mount issues so 37mm is the most I can run on that bike. With different fenders I might have been able to get 42mm to fit, but instead I built up the other bike.

You said that the tour includes 700km of gravel but you did not mention how much pavement. Last summer I used the Schwalbe Extreme on the rear and the Dureme on the front, both were 26X2.0, see photo. That worked great on gravel but if I had much pavement I would instead run the Dureme on both front and rear because the Extreme is not intended to be a great tire on pavement, quite noisy.

203345

With that much ruff stuff, bigger the better. I'd take a spare for just in case.

Also, the image conjured by "gravel roads" varies. If what is meant is "degraded-chip-seal", then 37-622 is fine. If what is meant is a "four-wheel-track-with-gravel-dumped-in-the-low-spots-for-drainage", then you'd want something considerably wider.

Also, the image conjured by "gravel roads" varies. If what is meant is "degraded-chip-seal", then 37-622 is fine. If what is meant is a "four-wheel-track-with-gravel-dumped-in-the-low-spots-for-drainage", then you'd want something considerably wider.

For the former, I like the Schwalbe Marathon Cross in 36mm. For the latter, I prefer the IRC Mythos in 42mm. I've put hundreds of rough miles on the Mythos and thousands on the Marathon Cross with 0 flats and excellent handling.

The total length of the trip is around 1,300 kilometres. The loose surface portion is, from what I've been told, decent enough in dry weather and miserable in the rain. Because it's also a stretch of road with little in the way of services, I want tires that can handle the trip.

I'll throw what little experience I have into the mix. I just did a short dirt/gravel over-nighter last weekend on my Sherpa and was very very impressed by how well the tires I have did. I'm running the WTB Pathway in 700x38(measure a little larger than that, about 41mm actual). They were great! Rode about 40 miles on pavement, and then another 40 on a mix of well traveled dirt roads, and some really rough mountain switchback road. Love the ability to run them at high psi for pavement for lower rolling resistance. I didn't even bother dropping them below 75psi for the dirt stuff, although it would've smoothed out the ride a bit.

On the "wet" side of the mountains I've found 1.5 's to work -ok- on most everything I would tour on. However on the east side you tend to get more dry sandy loose conditions. My 1.5's were just plain icky on sections of last summers KVR adventure.

We normally run slicks of 26x1.5 but when we take to gravel for extended times, we change to 26x2.0 offroad tyres, which give good handling in the gravel, but are not good on seal.

Continental Travel contact is a very good tire .
low rolling resistance smooth wide center band,
row of knobs on the edges
+their Gatorskin sidewall reinforcing.
622-37

Or 26-1.75

I replaced 26 x 1.75 Continental Travel Contacts with 26 x 2.0 Schwalbe Duremes. The Dureme from my experience is a faster rolling tire. The Continental Travel Contact may provide better flat protection because there is a lot of rubber on the rolling surface.

The total length of the trip is around 1,300 kilometres. The loose surface portion is, from what I've been told, decent enough in dry weather and miserable in the rain. Because it's also a stretch of road with little in the way of services, I want tires that can handle the trip.

Not all gravel roads are the same. I've found those in Canada and US to be pretty reasonable, except in some cases where they don't stand up to extended rain & turn into mud. However, in those overall conditions I've found 700x35 to be reasonable for me. This includes cycling the Dempster Highway (Dawson City to Inuvik) and the Dalton Highway (Fairbanks to Prudhoe Bay).

In other countries or perhaps less well maintained gravel roads, I've also used 700x35 but sometimes wished I had a slightly wider tire. For example, cycled the trans-Siberian Highway with a lot of gravel between Chita and Khabarovsk and would have appreciated slightly wider tires. On other hand, my cycling partner was riding 700x25 so it could still be done on narrower tires but not as comfortably.