yet another "help me identify this frame"


Dirt Disciple
Hi all,

I am embarrassed to post this, however I too would like some help to identify an unknown frame I have bought.

What I do know:
its a 23 inch frame (BB centre to seat pinch bolt centre)
It has no mudguard eyes,
The steerer tube is stamped "reynolds 531 butted 16.13"
It has a "divers helmet" rear gear cable stop - which needs a stepped ferrule; (an Italian feature?)
it has a 3/8 drain hole, tapped UNF thread in the bottom bracket with a plastic plug (UNF == USA?)
The bottom bracket has EO in a diamond stampede in to - the trademark of the Otsuya Iron Works in Japan, I believe
The Frame and forms are both stampede with the number 4701 so I assume they match.
It has Campag dropouts, and the drive side rear is drilled for a Portacaena chain hanger
The seatstays have long scallops
the seat clamp is threaded to take a metric bolt
the bottom bracket is 68mm and BSA threaded
the steerer tube is British threaded
it has brake cable bosses on top of the top tube
downtube gear leaver bosses
A chain hanger boss on the drive side seat stay
it has gear cable bosses on top of the bottom bracket
frame weight 2.1Kg bare but painted (531db, possibly 531c given its size and paint?)
fork weight 725g bare but painted
The seat tube is somewhere between 27.2 and 27.4 - currently I am using 27.2 with a thin shim.
it has a silva 189 brake bridge (a box in the middle of the tube drilled for a large diameter recessed brake nut)

from my investigations I have been told it could be an early Cougar frame from the mid 1980s, though I doubt that given the japanese BB and I think the over BB gear cables dates it more to the 1970s.

I bought it painted and scraping away a little of what is there it seems to have been blasted leaving no trace of its earlier identity.

This is my daily ride and I have no intentions of selling it, I am just very curious as to what it is.

Thanks for any help,



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Dirt Disciple
yes, I have fitted 700c's.

Actually there is minimal clearance for a 700c back wheel, the front a bit more generous.
I forgot to add earlier, 72deg head tube, and 73deg seat tube angles - which give you an idea
of its market - racey style but not a thoroughbred IMHO.


Dirt Disciple

anyone even recognise the seat lug and the long scallops on the seat stays?

does it remind anyone of French / Italian / Japanese / USA frames?


Senior Retro Guru
The scalloped stays are similar to those on a Dawes Galaxy but I don’t think it’s one of those. Angles are similar but I don’t think they have that brake bridge and there would be clearance for mudguards.


Dirt Disciple
thanks, i dont think its a touring frame,
there are no mudguard or rack bosses and the fork trail is too short.

i have a holdsworth mistral i bought new in 83 so i have a something to compare. this bike is quite a bit twitcher and “faster” feeling, though still not like the memory of the holdsworth team bike i rode once, that was in a different league.

i think the scalloped stays, the japanese bottom bracket shell, and the unusual seat cluster are the most distinctive featues of the bike.