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marshg246

marshg246

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I have three 850 frames with frame numbers (stamped in the headstock) that are confusing.

1974 850 Roadster, 310311, Italian Frame: 850 F104741 Does have rear gussets. Original owner says it is the original frame. The factory record is not available for this bike.

1974 850 Roadster, 320691, British Frame: 850 F114572 Does not have rear gussets and factory record shows that this is the original frame.

1974 850 Roadster, 307542, British Frame: 850 F100794 Does have rear gussets. This bike is a bitza so I doubt that the frame and engine went together.

The gussets imply that it is a MKIII frame, but it does not have a MKIII frame number. I'm sure that the frame came from the factory the way it is. All three frames have the ball before and after the 850.

My determination of Italian or British came from here: http://atlanticgreen.com/commandoframes.htm He calls the frame number a batch number which I'm guessing is correct - not really a frame serial number before MKIII. Anyone have any more info on this?


More on frames
 
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Your No1 is 90 odd lower than my MK2A 310XXX and mine has the extended gussets at the top shock mounts, the F number on my bike is 500 lower than your No1 which suggests stock control and sequencing was not good. Why your does not have gussets on a later frame (going by the F number) is odd as mine is Italian too but if the sequencing was bad then possible if the Italians stamped the frames just before loading them and the change happened near that time period. This is compounded by your even earlier British frame having gussets.
 
L.A.B. said:
Not if the extended gussets are like the ones on that drawing as they are not Mk3 type, however the Mk3 pattern plates were used on some late Mk2/2A frames.

Mk3
https://andover-norton.co.uk/en/shop-details/20476/frame-rr-susp-lock-bracket-mk3-
Click to expand...

The drawing section I included came from the MKIII parts page on AN - yes, I know that parts drawings are a terrible thing to go by. The pre-MKIII drawings are different. I think you are showing the enhanced replacement bracket (you know I'm not the expert).
 
kommando said:
our No1 is 90 odd lower than my MK2A 310XXX and mine has the extended gussets at the top shock mounts, the F number on my bike is 500 lower than your No1 which suggests stock control and sequencing was not good.
Click to expand...

The frames were probably just selected at random from the stack and why 'frame' and engine/plate numbers don't follow in sequence.
 
marshg246 said:
I think you are showing the enhanced replacement bracket (you know I'm not the expert).
Click to expand...

No, that is the Mk3 (and some late Mk2/2A) bracket. That "Mk3" drawing simply wasn't updated.

Edit: It wouldn't be possible to fit the Mk3 hinged seat and seat lock without the "Mk3" brackets.
 
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L.A.B. said:
The frames were probably just selected at random from the stack and why 'frame' and engine/plate numbers don't follow in sequence.
Click to expand...

Any opinion on if they were actually frame serial number or frame batch numbers?
 
L.A.B. said:
No, that is the Mk3 (and some late Mk2/2A) bracket. That "Mk3" drawing simply wasn't updated.
Click to expand...

OK, but my frame looks exactly like the drawing and my other frames look exactly like the pre-MKIII drawings. My frame does not have a replacement bracket.
 
marshg246 said:
OK, but my frame looks exactly like the drawing
Click to expand...

Yes, it should, as it's a Mk2/2A frame with the standard Mk2/2A extended inner plates (below).

2/2A
https://andover-norton.co.uk/en/shop-details/20497/frame-r-susp-mount-plate


marshg246 said:
and my other frames look exactly like the pre-MKIII drawings.
Click to expand...

Not really "pre-Mk3".
AN have used the '73 drawing for '74 as they often do because there was no illustrated '74 parts book so what you are looking at there is not the 2/2A frame but the earlier frame.


marshg246 said:
My frame does not have a replacement bracket.
Click to expand...

Hopefully, the above explains?
 
marshg246 said:
1974 850 Roadster, 310311, Italian Frame: 850 F104741 Does not have rear gussets. Original owner says it is the original frame. The factory record is not available for this bike.


1974 850 Roadster, 320691, British Frame: 850 F114572 Does not have rear gussets and factory record shows that this is the original frame.
Click to expand...

Edit:
I can't give you any reason why those frames do not have extended plates.
 
L.A.B. said:
Yes, it should, as it's a Mk2/2A frame with the standard Mk2/2A extended inner plates (below).

2/2A
https://andover-norton.co.uk/en/shop-details/20497/frame-r-susp-mount-plate




Not really "pre-Mk3".
AN have used the '73 drawing for '74 as they often do because there was no illustrated '74 parts book so what you are looking at there is not the 2/2A frame but the earlier frame.


Hopefully, the above explains?
Click to expand...

Of course! You always do make me understand - at least about the drawings!

So to be sure I do, you think the one with the gusset is a late MK 2/2A? My MK2A is 310311 so fairly early and it does not have the gussets. Also, the lowest numbered frame I have is the one with gussets so that part is still confusing to me.
 
I worked in a UK auto factory 10 years after the end of Norton in Production and Material control, WIP levels were high and control of old vs new stocks outside of model year changeovers was low, to see mods introduced on the frame but then out of sequence on the build line is more likely than you think. The frames were being made in 2 places, inside the UK and also in Italy which only adds to the possible mixing of old and new frames. As there were no related parts it would have been a low priority and loosely controlled introduction when I was controlling modification introductions, a simple make sure the new gussets were in stock, the old ones deleted from the parts list and the new gussets being welded to frames, tick the box as in production and move quickly onto more complicated mods. Don't see why Norton would do any different. All it needed was for one night shift in the Uk or Italy to find a stock of old gussets in an operators secret stash in case of shortages and a few old frames get made.
 
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marshg246 said:
So to be sure I do, you think the one with the gusset is a late MK 2/2A? My MK2A is 310311 so fairly early and it does not have the gussets. Also, the lowest numbered frame I have is the one with gussets so that part is still confusing to me.
Click to expand...

Yes, I certainly can't explain it as the one with the extended gussets (307542) would be quite an early Mk2 (from 307311) and the others, by rights, should have them.

According to the parts lists, the 850 Mk1 frame part number was 06-4140 and by Mk2/2A it's 06-5404 (the part number usually stamped on the front face of the LH fuel tank bracket).

The 850 Mk3 frame is 06-5632.
 
L.A.B. said:
Yes, I certainly can't explain it as the one with the extended gussets (307542) would be quite an early Mk2 (from 307311) and the others, by rights, should have them.

According to the parts lists, the 850 Mk1 frame part number was 06-4140 and by Mk2/2A it's 06-5404 (the part number usually stamped on the front face of the LH fuel tank bracket).

The 850 Mk3 frame is 06-5632.
Click to expand...

Recap with frame part numbers and a correction:

1974 850 Roadster, 310311, Italian Frame: 850 F104741 Part: 06.4140 Does have rear gussets. Original owner says it is the original frame. The factory record is not available for this bike. Note correction - before I said does not have rear gussets - it does - I looked at the 72 sitting next to it and got confused.

1974 850 Roadster, 320691, British Frame: 850 F114572 Part: 06.5632 Does not have rear gussets and factory record shows that this is the original frame. So, this is even more confusing now - the frame number is < 125000 but has the MKIII part number and the older shock mounts, no gussets and certainly not the MKIII mounts.

1974 850 Roadster, 307542, British Frame: 850 F100794 Part: 06.4140 Does have rear gussets. This bike is a bitza so I doubt that the frame and engine went together.
 
marshg246 said:
Recap with frame part numbers and a correction:

1974 850 Roadster, 310311, Italian Frame: 850 F104741 Part: 06.4140 Does have rear gussets. Original owner says it is the original frame. The factory record is not available for this bike. Note correction - before I said does not have rear gussets - it does - I looked at the 72 sitting next to it and got confused.
Click to expand...

Ah, not quite so mysterious then.


marshg246 said:
1974 850 Roadster, 320691, British Frame: 850 F114572 Part: 06.5632 Does not have rear gussets and factory record shows that this is the original frame. So, this is even more confusing now - the frame number is < 125000 but has the MKIII part number and the older shock mounts, no gussets and certainly not the MKIII mounts.
Click to expand...

I spoke too soon.


marshg246 said:
1974 850 Roadster, 307542, British Frame: 850 F100794 Part: 06.4140 Does have rear gussets. This bike is a bitza so I doubt that the frame and engine went together.
Click to expand...

Well, F100794 does seem a little early for it to have been the original frame for 307542.
 
marshg246 said:
1974 850 Roadster, 310311, Italian Frame: 850 F104741 Part: 06.4140 Does have rear gussets. Original owner says it is the original frame. The factory record is not available for this bike. Note correction - before I said does not have rear gussets - it does - I looked at the 72 sitting next to it and got confused.
Click to expand...

Very similar to my 850 mk2a
Frame is 39 younger but has MK3 shock mounts not the extra gusset though and engine number is 280 older.

Using the Dyno Dave info the frame is approx Jan '74
Engine would be early Nov '73
 
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Jungle_re said:
Very similar to my 850 mk2a
Frame is 39 younger but has MK3 shock mounts not the extra gusset though and engine number is 280 older.
Click to expand...

Previously, you said the 104xxx number was on the plate but it should be stamped on the frame......

Jungle_re said:
The red plate doesn't have a F mark but is a 104.........Number and the engine a 3105...
Click to expand...

...which suggests the original frame has been replaced with a Mk3 item and a new plate stamped to match the registration document, as you said yourself....

Jungle_re said:
The bike a mk2a 850 has possibly been repaired or replaced framed as although the plate matches perfect in the age parts to engine on dynodaves site it has several feature of the MK3. The extended braces on the shock mounts with *the ignition holes but on both sides (MK3 just on one side normally)* and the slot hole on the steering lock.
Click to expand...

*(As I stated previously, they aren't "ignition" holes and the Mk3 frame has extended plates on both sides, the LH outer and RH inner.)
https://www.oldbritts.com/13_065632.html
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The Mk3 frame LH inner plate also has an access hole for the seat front hinge nut.
https://andover-norton.co.uk/en/shop-details/20477/frame-r-susp
 
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You are correct in what you said above. However. The plate matches the registration document so irrelevant to the frame the numbers do no show up on searches and the records from the DVLA as being changed. So the numbers on the plate and engine as much as I can currently prove have been the same since it's registration.

The frame might not match the plate( thought it could well do) but I won't be able to find out till Im noi get floating half way between Norway and Denmark. I'll update the info once I've taken the plate off and the paint if I can't find it behind. Also to measure if italian or British.

The engine and plate numbers though tie in well with the numbers of the op first bike. But granted the plates may or may not be relevant depending on what the frame finally reveals itself as.
 
Jungle_re said:
You are correct in what you said above. However. The plate matches the registration document so irrelevant to the frame the numbers do no show up on searches and the records from the DVLA as being changed.
Click to expand...

No, I wouldn't expect it to show up anywhere especially if it was done some years ago but if the frame has been changed and a replacement plate stamped with the original frame number then as far as the documentation is concerned nothing has been changed.


Jungle_re said:
So the numbers on the plate and engine as much as I can currently prove have been the same since it's registration.
Click to expand...

Well, from what you have said, I somehow doubt the frame is original but most likely has been 'plated' with the original frame number.


Jungle_re said:
The frame might not match the plate( thought it could well do) but I won't be able to find out till Im noi get floating half way between Norway and Denmark. I'll update the info once I've taken the plate off and the paint if I can't find it behind. Also to measure if italian or British.

The engine and plate numbers though tie in well with the numbers of the op first bike. But granted the plates may or may not be relevant depending on what the frame finally reveals itself as.
Click to expand...

If it was a 'new' replacement frame then it probably has no number.
 
L.A.B. said:
Well, from what you have said, I somehow doubt the frame is original but most likely has been 'plated' with the original frame number.


If it was a 'new' replacement frame then it probably has no number.
Click to expand...

In at least part of 1974 the dispatch records include the frame number along with the machine serial number. I would be very interested if those who have those records would chime in with what frame when with their bike originally. I know they cost too much from AN, but I buy them for every bike I build. Unfortunately, there are some serial number ranges in 1974 that AN doesn't have.

Also, I'm never sure everyone is talking about the same things The engine number, gearbox number, and certification plate number should all have the same serial number. The frame number might have started matching those three at some point, but they don't on any factory record I've seen.

Finally, does anyone know for sure that the frame number is unique to each frame or if it is really a frame batch number as some have said.
 
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