531 is a material designation, not an indication of a guage. there were at least 3 different guages for all the tubes comprising the set. builder's choice, as always. you likely have a mid-guage seat tube. also, seat tubes are reamed following the build. the ream could have been 'set' for a 27 post if that was the most available post that month in honor oak park, london. e-RICHIE http://www.richardsachs.com
On Wed, 06 Jun 2001 15:52:13 -0600 Dave Denbow <denbows@prodigy.net>
writes:
> -Greetings-
>
> A couple of things. 1) I was at the local second hand store the
> other day and noticed a bike called a Bimex. Said it was made in
> mexico. Anyone ever heard of these? It was nothing fancy but it
> had this great handlebar attached waterbottle cage I really wanted.
> Almost wished I had a few tools with
> me so I could do a quickie while no one was looking.
> 2) I have a 73 Ron Cooper that I am restoring. I want to replace
> the off-brand seat pin it had with a campy two bolt model. Funny
> thing is, the diameter is 27 mm and not 27.2. I thought the 531
> frames from the UK were always 27.2 mm. Am I mistaken?
>
> Thanks much,
> Dave Denbow