Greg,
There's a couple of comments in the archives but no answers to your questions.
http://search.bikelist.org/
I started riding sewups again last year after about a 20 year break. Most of my old tubulars were toast so I decided to give the Servizio Corsas from Yellow Jersey a try just to get going again. At 3 for $50.00 it was worth a shot.
If you get some of these tires mount them on rims to check out the roundness first. If they're bad Andy will replace them if they haven't been glued.
Of the 6 or so Servizio Corsas I bought last year, 2 looked a little pregnant and one wasn't real straight. I used those on the rear wheels on several bikes and never noticed any difference in the ride. Don't expect too much from a $16.00+ tire.
On the first hill I remembered why I rode sewups back in the day. These are 19-20mm cross section tires. I used to ride Clement Paris-Roubaix red label cotton tires with about a 28mm cross section so these Servizio Corsas felt a little different.
So far they seem to be holding up OK. I only ride sewups in areas where there's a lower probability for flats. I avoid riding them in known goat head areas.
For what they are they're worth the money. I have some better quality tires I'll be switching to when they go flat. ;-(
Chas. Colerich Oakland, CA
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