I believe that the oversize Raleigh seat stay caps were a purely cosmetic feature to differentiate their frames. There is no functional or aerodynamic benefit. I think it was quite widely used on a number of their higher line bikes -- it appears on a 1980 Worksop-built Team that I have, plus a couple of Ilkeston-built 753 frames with serial numbers over 2000 apart (sorry I don't know what that represents in years) - the numbers are SB3675 and SB5949 if someone can tell us when they were made.
These seat stay caps are quite quaint, if not as distinctive as the old Raleigh fork crown.
HughThornton Cheshire, England
In a message dated 22/10/04 09:33:54 GMT Daylight Time, Carb7008@cs.com writes:
> I've often wondered if any listers know of other bike frames that were made
> like the Professional Mk IV with the oversize oval plates that finish the
> of the seat-stays? They seem so odd, almost as if the factory didn't want to
> take the time to grind the plates flush. Yet, I doubt this reason since this
> close to, if not, their top model. They took the time to slightly wrap them
> around. Could it be just cosmetic in order to distinguish it from
> there a dedicated Brooks tool-bag that used the lips for
> attachment...something to do with laminar flow?