Schwalbe's ZX versions of the popular Ultremo are competition tyres, they provide good grip and they're very, very fast.
Notice, though, that I described these as 'competition tyres', and Schwalbe do the same. The tread really isn't thick, hence a weight of just 190g per tyre on our test pair (even lower than Schwalbe's claimed 195g). The rubber doesn't wear away particularly fast, it's just that there's not much of it to start with, so if you're after longevity, these ain't the tyres for you.
What these tyres do best is roll fast. As well as the light weight, Schwalbe reckon that's largely down to their RaceStar Triple Compound which they say is their most advanced mix. They could be right, I couldn't say for sure, but what I can tell you is that these spin up to speed in no time and hold that speed effortlessly. These are right up there among the fastest clinchers I've ever used.
The carcass is made from 127 TPI (threads per inch) nylon and it's pretty supple. Schwalbe have added a little extra material to the tyre shoulders compared to earlier versions of the Ultremo, and that's added 15g to the weight but, as I said, there's still not a lot to these. Despite that slight weight gain, Schwalbe reckon these tyres have 15% lower rolling resistance than before.
The Ultremo ZX features Schwalbe's HD Speed Guard puncture prevention technology – the HD standing for 'high density'. It's surprisingly effective considering the low weight of these tyres. Using my highly sophisticated patented drawing pin test, I can tell you that the 10mm strip down the centre of the tyre – the bit between the silver stripes – is very resistant to sharp stuff.
Either side of that, in contrast, the tyre is pretty vulnerable, so if you're unlucky enough to hit something jagged while you're cornering, you might well be in for a bit or roadside tube changing. The sidewalls are very skinny too, so if anything flicks up there's a fairly good chance of it getting through... but that's the price you pay for the low weight.
The Ultremos are completely slick but don't let that put you off – a smooth tyre provides better grip on the road than one with a patterned tread because the area of contact is larger. I've never had a problem with the grip here. Even on damp roads, I've found these surprisingly sure-footed.
Fast, lightweight tyres with good grip and puncture protection, but save them for competition use
road.cc test report
Make and model: Schwalbe Ultremo ZX tyre
Size tested: 700x23C
Tell us what the product is for, and who it's aimed at. What do the manufacturers say about it? How does that compare to your own feelings about it?
Schwalbe say, "As tyre designers the Ultremo is the pinnacle of our ambition. We strived relentlessly to increase its speed and installed the ZX with HD Speed Guard and RaceStar Triple Compound. Both components are perfectly tuned to the requirements of an outstanding competition tyre. The result: Significant reduction in rolling resistance. Even so we used additional material to reinforce the tyre shoulders and to ensure a considerable increase in mileage. ZX - the best Ultremo ever! "
As Schwalbe say, this is a competition tyre: it's intended for going fast, not the ultimate in longevity.
Tell us some more about the technical aspects of the product?
This is what Schwalbe say about their HD Speed Guard puncture prevention system:
"HD stands for High Density and this new version of the tried-and-tested Schwalbe, aramid HD Guard is completely tuned for speed. Effective protection is achieved by using a patented technology that Schwalbe developed together with the US firm Warwick Mills, which holds 14 international patents for its high density weaving processes and is a world leader in innovative, industrial textiles.
"It is the finest and densest fabric on the market. No other bicycle tire protection belt gets anywhere near its weave density," said Schwalbe technician, Markus Hachmeyer. By utilizing this innovative technology for the first time it has been possible to create an ultra-light, extremely puncture resistant tire and this latest Ultremo version with HD Speed Guard enjoys the same high-density protection as its predecessor, but with distinctly reduced rolling resistance."
The main point of this tyre is that it goes fast and it does that very successfully. Just remember that this is a competition tyre, not one that's intended for everyday use, so speed rather than longevity is its strength.
The lack of material means its not especially durable although it's fine for a race tyre
Tell us how the product performed overall when used for its designed purpose
Very well; it's super-fast.
Tell us what you particularly liked about the product
The light weight/lack or rolling resistance.
Tell us what you particularly disliked about the product
Those sidewall are pretty susceptible to damage.
Did you enjoy using the product? Yes
Would you consider buying the product? Yes, and I have bought previous incarnations in the past
Would you recommend the product to a friend? Yes
About the tester
Age: 41 Height: 190cm Weight: 75kg
I usually ride: My best bike is:
I've been riding for: Over 20 years I ride: Most days I would class myself as: Expert
I regularly do the following types of riding: time trialling, commuting, club rides, sportives, general fitness riding,
Mat has worked for loads of bike magazines over 20+ years, and been editor of 220 Triathlon and Cycling Plus. He's been road.cc technical editor for eight years, testing bikes, fettling the latest kit, and trying out the most up-to-the-minute clothing. We send him off around the world to get all the news from launches and shows too. He has won his category in Ironman UK 70.3 and finished on the podium in both marathons he has run. Mat is a Cambridge graduate who did a post-grad in magazine journalism, and he is a past winner of the Cycling Media Award for Specialist Online Writer.