raleigh rod brake linkage

[delap]

I have a 1922 Raleigh DL1 (based on K3 hub serial number KK 70259 and this source).  The rear brake linkage has a typical pivot at the head-down tube joint (19 in the image below) but nothing at the down tube-bottom bracket.  The rod simply bends around the BB shell and attaches to the top of the brake stirrup rather than have another pivot joining two straight rods (part 22 below).  There is no drilling at the bottom of the down-tube for a pivot, nor any marks in the paintwork suggesting a band-on assembly.


I am wondering if the current arrangement is original.  It seems very springy and really doesn't transmit movement to the stirrup well (even by the standards of rod-brake systems).  Can anyone point to a resource that might shed any light on the likely original configuration?  I have another rod brake bike (an Elswick Hopper model W trade bike) which has a pivot that bands onto the bottom of the seat tube.  A lever hangs down from this behind the BB and is attached to the down-tube rod and brake stirrup similar to this:


Could my Raleigh have had a similar mechanism in the past?

edited to add illustrations

[Brucey]

this might help;

http://www.oldbike.eu/museum/1920s-3/1921-2/1921-raleigh-all-steel-modele-superbe-x-frame-green-enamel/

http://www.oldbike.eu/museum/1920s-3/1923-2/1923-raleigh-all-steel-modele-superbe-x-frame/

since it appears to have a similar setup to the one you describe. The idea may well be that you keep it adjusted so that minimal movement is required to apply the brake; this will reduce the bending stresses in the rod (where it passes round the BB shell) to a minimum.

There are lots of other bikes on that website and the site owner may respond to queries by e-mail.

cheers

[delap]

Thanks Brucey.  Oldbike.eu is a great resource for vintage bikes.  It looks like my setup is pretty standard on 1920s Raleighs

[Brucey]

in fact since I posted I mentioned this to one of the most experienced cycle mechanics locally; he has worked on several such bikes and agreed that adjusting the brakes regularly was the key with this system. He also mentioned that (amongst other things) he'd

a) made a new rod from similar wire (which suggests that the originals can and do break, as you might expect) and
b) replaced the rod with a Bowden cable inner, which was (if well greased at the BB) a considerable improvement.

cheers