Help dating Birmingham Sun frame

[3wheeler7]

Hi, just looking for some help to put a date (and model?) to this Birmingham made Sun frame.
Ignore the forks as they're obviously a later addition but the frame number is a bit confusing from the data I can find.
Frame is clearly stamped 477NM on the lh drop out, but all the data I can find shows a only single year letter - e.g. M or N but not both. M = 45/46, N = 46/47.
Any clues? Do I suppose it's a 46?
Will be putting it up for sale on here so trying to confirm the year.
Thanks.

 

[bagpuss]

Have you seen this date list for sun frames made in Birmingham ?


My Sun Manx tt worked out to be 1951 . I think it was old tel on this forum who gave me this info .

Track end on Sun Manx tt by rebalrid, on Flickr

 

[3wheeler7]

Hi bagpuss, yes I've seen that list and from that I deduced that my frame is either M = 45/46 or N = 46/47, but were bare gear cable braze ons on the BB shell and bare brake cable braze ons under the top tube around as early as that? I know they could have been added later.
Ref your frame number - you're assuming it's a 51 due to the S in the frame number but I read somewhere that the S means a special build and that would make yours an L = 44/45 frame.
I've emailed the V-CC Sun ME to see if he can help.

This is the first of a few old lightweight frames that I picked up and I'm researching. When time allows I'll start new threads for each of them, some have no identifiable marks but may be familiar to some of our older members!

 

[keithglos]

Looks like a Sun Wasp early to mid 1950s. Check the seat post diameter, probably butted 531, so 27.2mm?
In the late 40s Sun still used their own cast lugs in better frames, Nervex were not common until 50s.

 

[3wheeler7]

Thanks Keith, but how would the frame number tie in with the chart?
The frame is in a friends lock up at the moment and he's away for a few days so I'll measure the set tube dia when he gets back and I can also take some pics of the other "beauties" we've acquired.
One of them is a Clifton Cycles (Liverpool) as per the pic attached.

 

[KermitGKona88]

It's from Birmingham, a couple of cans of Stella should do the trick...

 

[bagpuss]

In reply to the op . I thought the same .ie S = special build . There is always different opinions on frame numbering and pre fixes . I have never got to involved .

It is a good looking frame you have pictured .

 

[3wheeler7]

If only we had the internet back in the 40s-50s, it would all be recorded............ but then there'd be nothing to ruminate on.

 

[Old Ned]

First time I've seen a Clifton on RB. One of the 'missing' brands! They were very popular with Birkenhead/Wirral area riders when I was a lad. I visited the shop once, opposite the Birkenhead Mersey Tunnel (definitely NOT Liverpool!) entrance I seem to remember. I've no knowledge of who actually built their frames whether it was 'in house' or a local builder as and when required. The lettering looks as if it originated at C&G finishes in Liverpool in their 'trademark' hand done style.

 

[Guinessisgoodforyou]

Thanks Keith, but how would the frame number tie in with the chart?
The frame is in a friends lock up at the moment and he's away for a few days so I'll measure the set tube dia when he gets back and I can also take some pics of the other "beauties" we've acquired.
One of them is a Clifton Cycles (Liverpool) as per the pic attached.

That looks nice