Instead of guessing, why not just measure it? In my experience, the seat-tube diameters often are not what they are supposed to be, anyway, and frequently they are not even perfectly cylindrical. Often, seat tubes aren't reamed, so they are just the nominal inside diameter of the tube, which may be a couple tenths of a mm off.
You can get an inexpensive dial caliper for about $15 and inside caliper for a couple $$ from MSC direct or Enco. I've found these tools to be among the most valuable I have.
Steve Maas Long Beach, California
jerrymoos wrote:
> I'm not so sure. 26.2, 26.4 and 26.6 were all very common sizes on high end
> French bikes in the classic era. In my experience, 26.6 is every bit as
> likely as 26.4.
>
> Regards,
>
> Jerry Moos
> Houston, TX
>
> ----- Original Message -----
> From: "Chris Van Scoyk" <parisbrest@mchsi.com>
> To: <Classicrendezvous@bikelist.org>
> Sent: Saturday, March 06, 2004 7:36 PM
> Subject: [CR]RE: Old broomstick in the seat tube trick
>
>
> Well George, my best guess for your seatpost is 26.4 . I've really never
> seen any other size for an early seventies Gitane. Doesn't have to be a
> French brand seatpost either just a 26.4. I have a few SR Laprades that are
> not that pretty, but I'll offer you one for the cost of shipping.
>
> Chris Van Scoyk
> Ankeny, IA
>
> _______________________________________________
>
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