I did a head-to-head today with my current champ, the CS clincher and an old tubular I mounted a decade ago.
Vittoria CS clincher: 25.1 mph; 52 watts; Crr: .00251
Vittorial Crono CS tubular 25.3 mph 54 watts, Crr: .00259
So the clincher wins by a hair. However, the Crono CS tubular soundly beats the Conti TT and the Turbo Cotton. I imagine a wider version of this tire would beat them all.
A few notes:
* The Vittoria CS clincher was mounted with a 10-year old Michelin 18-20c latex tube, known as "Old Greenie"
* The tubular is spec'ed as 20C. It measures around 20.5mm.
* The wattage for the CS clincher was lower than in previous trials because I lost 5 pounds and switched to a TT bike.
* The tubular was glued on with either shellac or Mastik 1 (after 10 years I forgot)
* The tubular is mounted on a Zipp 808, the clincher on a generic semi-aero 30mm deep rim.
* Pressure was 120psi
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