Can a piece of rubber, nylon mesh and a bit of aramid fibers bring you happiness?

We did over 36000 kilometers using Schwalbe’s discontinued “XRs”, “Duremes” and “Mondials” on our rigid steel bikes. As we progressed across Asia towards Australia, we started to find more joy on all those little paths and tracks and did more adventures than we planned when we set off. When we have learnt about the release of the new off-road touring tires from Surly, the ExtraTerrestrials, we knew that they will change the way we travel. As soon as they were available on the US market we bought a set of 4 and had them shipped to New Zealand.

Review Surly ExtraTerrestrial

gettingnowhere Surly ExtraTerrestiral

What a joy!

Surly Extra Terrestrial Tires

As we opened the box, we discovered, that the quality of the tires was matching the one of the tires of a German producer. The sidewalls were pleasantly thick, the knobs well spread out, with a distinctive arrow pattern in the middle of the thread. You can check the diagram of the tire here. Most importantly (for touring cyclists) they have a puncture protection, a kevlar belt making them “real” touring tires. We decided to run them with tubes, as we used to with all our previous tires. They are perfectly fine tubeless as well.

Surly ExtraTerrestrial vs Schwalbe Mondial

When mounted on our wheels and pumped to 3 bars, the tires looked huge in comparison with the Mondials!

Surly ExtraTerrestial Andra Rigida CSS

It was fairly easy to put them on the Andra 30 rim from Rigida (now Ryde). It is a fairly narrow rim, but a classic for long distance tourers. The tire mounted on a rim like that has a rather round profile. There was much more air in the tires, luckily we had a compressor at hand!

Surly ExtraTerrestrial 26 Rohloff Schwalbe Marathon Mondial

Surly claims, that you can pump them rock hard – to 4,1 bars, but check your rim allowance before doing so! We have pumped it to 3 bars and found it super hard – a quick ride on dry pavement with wet tires left a mark of only the middle section of the tire. That means – low rolling resistance on tarmac!


Surly ExtraTerrestrial Bikepacking

The tires, when mounted on 26′ rims were slightly higher (26,5′) and much wider, of course, than our previous ones.

We have measured our frame space before the purchase and both bikes could fit the tires just fine (Patria “Terra” and Thorn “Nomad Mk2”). We highly recommend doing so to avoid disappointment.

Our only concern was the space between the Tubus “Carry” rack – only a millimeter of a gap was not enough and we had to do some gentle bending to have a bit more space. The “Logo” was fine.

Surly ExtraTerrestrial Thorn Nomad Patria Terra

We started the test on paved roads, with tires pumped to 3 bars. We felt no increase in the rolling resistance on asphalt. On the downhills, due to the weight of the tires (almost 200g of a weight increase per tire!) we could feel a bit of a gyroscopic effect – the tires were more stable but also a bit less nimble (but not very noticeable). On the uphills we could feel a bit of an increase in the rolling weight, but to be honest, those things matter slightly less when you ride a fully loaded, touring bike.

A true test for the tires was our first beach ride. We tried that before, with our previous tires, but with little success.

Surly ExtraTerrestrial Sand

Surly ExtraTerrestrial offroad

To our surprise, ExtraTerrestrials, when we lowered the pressure to less than 1 bar, allowed us to ride on packed beach with ease, and on loose, deep sand we were able to ride the bikes downhill without digging into it. They are far from being as agile on sand as proper fat tires, but to call them semi-fat is spot on – they allow a fully loaded, heavy bike to be at least pushed over loose sand, and that in the world of adventure touring, means a lot!

Schwalbe Mondial vs Surly ExtraTerrestial

As a matter of fact, we covered over 150 kilometers on various beaches of the northern part of New Zealand, including the famous Ninety Mile Beach. During the low tide we were doing a steady 19km/h.

Surly ExtraTerrestrial whale

Surly ExtraTerrestrial 26 wide

ExtraTerrestrial 26 plus

ExtraTerrestrials wide profile allowed us to explore areas, where we would never be able to ride with the standard 2.0 inches wide tires.

Beach riding Surly ExtraTerrestrial

Surly ExtraTerrestrial unpaved

But where the tires really shine is gravel. We love gravel. If possible, we choose unpaved, bumpy roads over bitumen. They always guarantee fun and adventure. The new rubbers gave us something that we missed quite a lot when travelling on dirt roads – comfort! With the pressure lowered to around 1,5 bars, the tires were squishy enough to absorb the vibration of the road; they also made small corrugations and even egg-sized stones disappear!

Surly ExtraTerrestrial gravel

With the right pressure, due to their volume, the tires provide a significant level of suspension. We both use suspension seatposts, but nothing isolates the rider better from the rocks and bumps than a decent amount of air in the tires.

Surly ExtraTerrestrial touring New Zealand

We realized how much it changed the way we ride one day, when we were going downhill on a slightly corrugated, gravel road. Not only we could fully seat on our saddles without the need of standing on our pedals (important when you ride a heavy bicycle), but when we checked the speedometer we discovered, that we were rolling 52km/h on a treacherous road without a slight of fear. The tires literally stick to the surface, we never skidded on curves (unless we wanted to), never felt insecure.

Surly ExtraTerrestrial 26 2,5

Surly ExtraTerrestrial mud

We tested the tires thoroughly, doing over 1000 kilometers on the roads and paths of the very North of New Zealand. Without doubt they are perfect tires for us and the other adventurous cyclists, who travel long distances on rough surface roads. We wish we had them in Australia during our recent crossing of the Center; they will also shine in the Himalayas.

Review of Surly ExtraTerrestrial

We had zero flats so far. The ExtraTerrestrials have a kevlar belt embedded in the carcass and so far we can say that it works. Will they last as long as the Mondials (12 – 15 thousands km)? Time will tell.

Are the ExtraTerrestrials worth a swap over more standard, Mondial tires? Definitely yes, if you are planning to do at least 20% of gravel roads. We highly recommend them for the Silk Route (especially for the Pamirs). We wish we had them with us when we did the Himalayas as well as in Australia, during our recent adventures.

We have been thinking more and more about getting new bikes, so that we could do some crazy stuff in the most remote locations. If Surly decides to release the ExtraTerrestrials in 29 3.0 we would sell our bikes straight away and build new machines.

We simply love our new set of rubber! We had a lot of fun using them and there was one moment, when after a long day spend on gravel roads we entered tarmac, and instead of being happy and relieved, we felt sad, cause we could no longer hear our favorite sound – the gravel being ground under the tires.