Sorting out a Norton Inter project

[cardan]

OK, I'm puzzled.

I'm helping a friend to sort out his shed, and one of the items is this Norton "Inter" project. The engine number is 64131 (which seems to give 1936 from my list - sounds OK), but the frame number 43739 has me baffled. I thought that Norton numbers in the 1930s were in the same range for engine and frame, but a plunger frame would have to be either late 1930s (1938/39) Inter, or perhaps postwar Inter/ES2.

Now in my list the years/first numbers go:
1937    69800
1938    81500
1939    87920

1945      1001
1946   A 2131
1947   B 7756
1948   C 13792
1949   D 20701

Can someone tell me what the frame is?

Thanks

Leon

[Bomber]

If I were you I would have a look somewhere on the spine under the front of the tank.. another number may well have been painted over. Its an Inter frame, an ES2 plunger would have its plungers more vertical.

[Bomber]

Might be a mis-stamp from 1952 with the missing letter???

[Norton55]

The frame number should be of the left side near the front tank mounts. Here is an example of what they should like. This one is from my spare 1948 Inter frame which is almost identical to the one posted above.

[cardan]

Ah you have to love old motorcycles! I've just been up to my friend's shed (between Weeties and a cup of tea) but there is no stamping on the left side of the front tank lug. By the way, the lug is quite different to the one on the 48 Inter as it is not a solid casting but quite an 'open' affair - photos later in the day.

When the day brightens a little I'll go over the frame in detail looking for another number. Other than numbers, is there any way to tell the difference between a pre-war Inter frame and a post-war Inter/ES2? Bomber mentioned the angle of the plungers...

Thanks

Leon

[Bomber]

Here's a picture of a 1950 plunger frame number

[R]

Do the steering stops for the frame match the girder fork stops ?

[Bomber]

I don't know.. never owned a girder version

[Bomber]

Note the plunger angle

[R]

I don't know.. never owned a girder version

Was asking Cardan !

[R]

Here's a picture of a 1950 plunger frame number

Thats the dodgiest frame number stamping/location seen for a long time.
Like quoting the casting number just under it, on the other side...

Norton55 showed the correct postwar location.

Is Cardans frame lightweight tubing ?

[Bomber]

Was asking Cardan !

No need to shout...

[R]

? ? ?

DIDN"T NOTICE I WAS SHOUTING ?!

[Bomber]

Suit yourself.

[cardan]

Thanks for suggestions.

I have scraped off paint in all the likely places, but the number I show in the first post is the only one I can come up with so far. Will try one more time before day's end.

Do the frame stops match the girder stops? Well not exactly, but the short stops on the frame do hit the bottom cross part of the steering head. If they had some slightly longer bumpers screwed in (instead of just slotted screws) the match might be better. It could be a tele-fork frame with girder forks; perhaps it is an early 1950s frame missing its letter prefix?

The frame is relatively heavy. While the large diameter tube in the front part of the frame seems to be nice quality, the smaller tube for the rear sub-frame seems pretty thick-walled and sounds "dead". I doubt very much its a racing frame, as it has sidecar lugs and a centre stand.

I'll post photos of the lighter tank mounting brackets later.

Leon