On test: Schwalbe Ultremo ZX.

The Ultremo ZX is the top of Schwalbe's Road Race tyre range and is part of their 'Evolution Line' which means that it recieves the latest tech and best materials. and as I was going to these tyres from some pleasing results on a pair of Continental GP4000 S tyres which I found very good on the grip and durability front, I had high expectations for these tyres. To switch to another brand after you get to know what you like requires a bit of a leap of faith. It's like changing your best pair of slippers to some new ones.

The Ultremo ZX is available in a rainbow of different colour options to colour match them to your bike, but I'm not a massive fan of coloured tyres and Schwalbe themselves say that the additives needed for these colours affect the grip level of the tyre and if you want the best levels of adhesion you should go for plain Black. Fine with me!

The tyre size I opted for was 700 x 23, my heart wonders if 700 x 25 would be any quicker given the current findings of wider tyres rolling faster, but I still find it difficult to get my head round this concept and would like to do some more research before hopping up a tyre width (the Ultremo ZX goes up to a 700 x 28)

You can run the tyres from the 85 - 145 PSI range, impressive for a clincher. As I weigh 11 stone I run 100 PSI in both front and rear tyres, dropping 5-10 PSI for wet conditions. They weigh in at a claimed 195g which is 10g lighter than the GP 4000 S and all the more impressive when you consider that they come specced with 'HD Guard' Schwalbes anti puncture liner which uses a High Density woven fibre belt (think Kevlar) as standard.
The yin to Continentals 'Black Chilli' yan is 'Triple Racestar Compound' which claims to offer minimum rolling resistance with maximum tack.


Breaking the folding tyres out of their box and popping them into shape I found they held their shape well and fitted the rim (Mavic Cosmic Carbone) with just the right level of snug, not too tight like the outgoing GP4000 S's were. They seated well under the track pump.

For the first 50 miles these tyres were a bit of a disappointment. I was used to really nailing the bike into the corners and the Ultremo ZX's felt slippery and unconfident. I believe this to be down to the release agent used in production when releasing the tyres from the mould and coats the tyre like a thin layer of talcum powder. I say this because after this initial bed-in period the grip levels started to rocket and I have to say they have surpassed the Conti's!

I have now done well over a thousand KM's on these tyres and they have been faultless. The grip level over all conditions has been confidence inspiring and the HD Guard has seen off some sharpies that would have written off lesser quality tyres. I've tentatively picked out shards of glass at the end of a ride waiting for the 'hissssss' that signifies true penetration, but it never happened. Happy Days!
The tyres are now looking well used and the rear tyre has flattened on the top section and is starting to feel a little 'edgy' leaning her over.

In these tyres I have truly found a 'new pair of comfy slippers' and I'll find it tough going to another brand from these now.