I thought there was an anomaly with the battery tray in my box of parts. L.A.B. identified it as a tray off a Commando S. As it turns out the frame looks like an S, also. The twist lock fastener for a removalble cover is on the right hand side. Rather than butcher it to fit, no doubt the best thing would be to find an S oil tank and keep the matching number S frame and crank case together and intact.
Both the frame and engine are 137717. Is there a reference that id's a serial number as a specific model?

littlefield wrote:As it turns out the frame looks like an S, also. The twist lock fastener for a removalble cover is on the right hand side.

Both the frame and engine are 137717. Is there a reference that id's a serial number as a specific model?

I think you have already identified it as being an S model frame?

However, you could contact the records and machine dating sections of either the UK VMCC, or the UK NOC, as both have access to the Norton factory records that remain?

I don't think the VMCC charge for giving out basic information, the NOC may do?
Don't expect an immediate response from either service.

http://www.vmcc.net/

http://www.nortonownersclub.org/


According to Roy Bacon's "Norton Twin Restoration" book, the S model started at serial 131257 and the last was 135088, which puts yours outside the normal range of S model serial numbers?

I think some '70 Fastbacks could have been built with the S model oil tank arrangement?

So maybe it was a Fastback originally, and not an S model?

The list I have, which is not verifiable, lists it as a Fastback MK II. My list shows the last S as s/n 135088 in June of 70. Then in Sept 70 the Fastback MK II but no serial numbers, so it may be one of those numbers that is hard to find.

Dave
69/70 S

Okay, thanks for the information.

Norvil shows engine number 131257 (I guess that's a series beginning with that number) as a 1970 Fastback S-Type Roadster with an engine seriel number preceeded by 20M3S which mine has. I reckon that's what I've got even though it's registered as a 71.

OK mystery solved I think?

As I've found a couple of photos in books showing early Roadsters which have the S type oil tank, so it's more likely to be an early Roadster model than a Fastback at least? And a Roadster model would be the most logical, as it originally started out as a low pipe S model.

littlefield wrote:Norvil shows engine number 131257.... as a 1970 Fastback S-Type Roadster with an engine seriel number preceeded by 20M3S which mine has. I reckon that's what I've got even though it's registered as a 71.

Well, its got to be one of them, (Fastback? S? or Roadster?) but it can't be all three?

Norvil's Commando model identification list is rather basic and incomplete, and therefore is slightly misleading, so the information as it's written isn't totally reliable, unfortunately.

I have an early roadster with some of the S-styling, like the ring around the headlight and more chrome than later roadsters, nr 20M3S 135676
It also has the S-battery tray. So it might well be an early roadster.
Mine is stamped dec69, which is strange since an earlier post mentioned a higher number for jun70....
regards,
Thomas

1968-1970 frames are all alike (except for the few '68 Fastback "widowmakers"). 1971 frames are different, having the centerstand mounted to the subframe rather than the frame, and a couple other small diferences. 1972-1973 750 frames are alike, as are 1973-1974 850 frames. The 1975 frame has slight differences. Of course this does not include English vs. Italian (Verlicchi?) manufacture.

In 1969 the 'S' was the only model to use the centermount oil tank. In 1970 they built the first Roadster which was essentially an 'S' with low pipes. This used the center mount oil tank. 1968-1970 Fastbacks all used the large side mount tank with the sight tube and no cover. In 1971 the Roadster and Fastback used the smaller side mount tank and side cover that continued until the end of Norton Production.

Hope this helps.