I just fitted some new, big tyres. They are Schwalbe Ultremo ZX in 28mm size. There aren’t many slick 28mm tyres that use proper fast compounds. I’ve previously used Continental 4 Season in 28mm and while they were ok, they didn’t last too well.
Then I tried Vittoria Rubino Pro Tech in 28mm these were pretty good but not fast.
Both of the above were “narrow” 28mm tyres. I think the Continentals were the bigger of the two and they were 26.5mm wide in reality.
I measured the Schwalbe after I’d fitted them and they are a genuine 28mm wide. They seemed to take more strokes of the track pump to inflate. So they must contain more air. Hopefully they will give a better ride. Without the Crud Roadrace mudguards on the Schwalbe tyres fit with plenty of clearance- as the photos show. They do have to be deflated to fit through the brake shoes however.
Update: I did use these tyres for PBP in 2011
Following the 1200km of PBP + a bit of riding around Paris before and after the tyres looked unworn except for a nasty “cut” in the sidewall on the front tyre. The “cut” went through the outer “rubber” layer but was stopped at the carcass.
When I got home again I put the Ultremo front on the rear and the rear on the front on my general knocking around bike. The tyres went to the pub several times by laney routes. By early the next year, after a few months and another 1500km both tyres still looked unworn except for a number of “cuts” as described above. There were a few of them in both the front and rear tyres. I didn’t like the look of them so I took them off and binned them. The tyres never had a flat or any other trouble. I bought some more on special offer from a German shop last year. The current version of the Ultremo is “improved” in some way.
I see that Schwalbe are going to do a 28mm version of their new “One” tyre. I assume this will replace the Ultremo ZX 28mm, but you never know with Schwalbe, they have a ridiculous choice of subtly different tyres