Help with unknown bike frame number

Steelframeman

Dirt Disciple
Hello from a newbie new to the forum, as now retired & been on bikes all my life, & many times in my searches its taking me to this worthy site, so here goes.
One of my hobbies is to find out scrap bikes & rebuild them as best a possible nothing super classic thought, normally it that situation they have been hand painted & all decals markings lost, I’ve actually 4 here now like that.
I’ve just finished rebuilding one, it originally only had the frame, rims, crank, brake calipers & RD, but being lugged with forge drop outs it was worth the effort. It’s without a doubt a UK bike, 25.4 mm seat post: UK ISO gauge size top tube, 68.mm BB, usual 24 threads per inch, rear chain stay spacing is 130.mm, & the seat tube is double butted, I cannot confirm the top or down tube
Of course in the 1980s Raleigh & several other major Asian frame builders were making bikes frames for everybody else, who then put their own decals markings, & a few bits to individualize them.
I think it’s a touring frame as the rims are wide taking (28 x 1”5/8 x 1”1/4) 700 x 32 tyres these are the smallest I could put on.
I’ve enclosed a photo maybe it’s a Hercules or something I’ve spent considerable time on the web trying to identify the frame number without any luck so I thought one last shot & hopefully someone here may recognize the number format:- Frame SU 89080470
 

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Can you get some close-ups of the lugs, fork and dropouts? That sort of thing usually helps identify bikes.
 
Re:

Appreciate all the views I've had, & as requested here are some photos of the lugs, I've shown them when the frame was being primed otherwise one can never see the detail, especially the rear drops outs.
These lugs I have to say are fairly mundane in design although they do actually have some small numbers punched on them, these lugs I've seen on several UK frame photos of that period, anyway hope these help.
 

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Clearly a mass produced frame. The seat tube would be 1.125 inches outside and 1 inch inside. If butted tubing the seat pillar would be 27.2 not 25.4, which indicates heavy seam welded tubes. You might be able to feel the seams from inside the bottom bracket. A butted seat tube would be single butted.

Seems to have a very high bottom bracket to allow making the frame small, and withing UK legal limits for crank to front wheel clearance.

Keith
 
Re:

Thanks for your comments, I assume the high BB is part of the touring frame set up, agreed mass produced, although it has forge drops outs. Just hoping someone recognized the frame number format.

For my own knowledge are you saying that it cannot be butted if its 25.4 mm so every 25.4 mm seat post size has to be rolled & seam welded ? as its assembled I'm not hopefully going to pull it down to check !
 
It's a very presentable bicycle and a nice overhaul, the frame configuration is unique and the construction is nice, has nice lines and I'm sure it attracts a bit of attention as it sort of looks like a small CX bike with that high bottom bracket. The fact the manufacturer is a mystery and the tubes are without pedigree is not a bad thing, you will never dent that frame unless a house falls on it. I would ride it and enjoy it, it's a nice bike.

: Mike
 
Raleigh used those lugs on their frames and forks, they're identical to the ones on my early 90s Strada, but They didn't use those round ends on the seat stays. My Strada also has those cast dropouts. The bend in the fork says to me that it's not a Raleigh, it's too high up the fork and too sharp a bend compared to the Raleigh ones which are a bit lower down and a longer bend. The notched seat post bolt says 80s to me. And yes, 25.4mm seatpost means plain steel tubes.
 

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