Seems to me that Peter Brown has quite a rare frame on his hands with this peculiar CB bi-lam. Many of the "Avant Coureur" models lacked a "lug" down the seat-tube, but I have not heard of any frames that only had lug "pipes" on the main triangle's tubes.
>From a logical point of view and bearing in mind the pressure points on a frame the reinforcement should have been placed on the head and seat tubes. Who knows.. it might have been a prototype... or a Friday afternoon frame?
If Peter is reading this contribution I would like to see some photos., please...
Norris Lockley.. revsing my ideas about bi-lams... Settle UK