Frame Plate Orientation Survey

marshg246

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I wasn't there, but have worked in a manufacturing environment, and currently still do, I do have a theory.
The steering necks are cut too to length, bored for the bearing pockets. If you pop them in a purpose built fixture, you can machine drill the 4 holes with precision. Then continue to have welded on the steering stops and steering lock tab. This piece goes to the frame assembly area to be incorporated in full frame manufacture.
Stove enamel in black.
Then when the frame gets to the bike assembly line, the frame is on its right side down . The little table or cart next to the assembly line with the number punches and box of cert plates and drive screws gets pounded in with a socket head punch. (matches the round head drive screws)
He then grabs the number punches and stamps the number in the cert plate which is in the up position. Writes it in the book? Frame goes "down the line".
Things would have changed if the production line changed or moved location. So this possible scenario could change over time.
Jan 1972 enter new cert plates after 2000+ combats already built.
Seems later production changed to the left side down for number stamping of the batch# as well as the VIN/SN
Just guessing what I would have seen if I was there-then.
Certainly plausible. Two data points that might slightly modify.

1) I have a label that I believe to be original that has the serial number (203143) stamped readable in the same direction as the printed label and the stamp is deep enough that it is doubtful that it was done on the frame. The date is stamped upside down and not deep at all. Also, it is stamped "1972 Jan". I have been guessing that , at least at that time, that the label was stamped with the serial number and then it was installed on the frame. The date was later stamped.

2) If you zoom into the picture here: https://andover-norton.co.uk/en/service/ you'll see that the label is already on the frame and the steering bearings are installed. That's a weak data point, but something to consider nonetheless.

The label is 06.3247 (according to AN)
 
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I'm very confident they were NOT hand drilled in the "frame prep area"? LOL The 4 holes were drilled before bearings and spacer tube installation.
You may be entirely right though it changes little as the man on the line would then pick up # stamped cert plates out of the box and drive screws them on the frame before it hits the final assembly line as shown the pix. Only a matter of sequence.
 
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Or just the operator changed and a right handed operator was replaced by a left handed one so he turned it around to suit.

Working in a Midlands car factory 10 years later there was a huge comotion one shift, 2 cars were issued with the same VIN. 8 guys rushed up into the conveyors carrying the bodies over to the engine and suspension line and lifted the body and laid it down on the safety net, it was up there for weeks whilst they worked out how to get it a new VIN and back into production.
 

marshg246

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I'm very confident they were NOT hand drilled in the "frame prep area"? LOL The 4 holes were drilled before bearings and spacer tube installation.
You may be entirely right though it changes little as the man on the line would then pick up # stamped cert plates out of the box and drive screws them on the frame before it hits the final assembly line as shown the pix. Only a matter of sequence.
100% on the drilling - I've never found one that wasn't properly drilled. I'm quite sure you are correct about (paraphrase) them making a sub unit with the steering stop and lock tab, holes drilled, and bearing machining done.
 
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MK3 1975 Commando is an original not tampered with bike. My plate is is mounted dead center on the tube but read from the chaincase side.

ELLIS
 

batrider

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'72 Combat roadster 202093 owned since new - 1972 JAN date, Andover plate. Plate is mounted closer to drive side on steering head, reads from timing side with stampings facing the right way. S/N stamp is straight and within the box. Date stamp is partly out of the box and not uniform depth.
I have a replacement blank plate that I got years ago (just in case) but didn't use. It matches the original. Maybe from Old Britts - I remember seeing a page where they were all in one place.
 
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'72 Combat roadster 202093 owned since new - 1972 JAN date, Andover plate. Plate is mounted closer to drive side on steering head, reads from timing side with stampings facing the right way. S/N stamp is straight and within the box. Date stamp is partly out of the box and not uniform depth.
I have a replacement blank plate that I got years ago (just in case) but didn't use. It matches the original. Maybe from Old Britts - I remember seeing a page where they were all in one place.
The saga continues o_O.... Andover plate sounds OK , stamped jan 72 a little out of sequence, but we weren't there ! 2021xx and 2022xx previously show Dec 71
I'm so far going with cert plate on left (drive side) is a imperial tube frame. ???custom production floor tagging "tag reads from timing side" is the out of normal part.
 
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Starting in late 73 the metric frames started to show up. They were mostly tagged on the right side (timing) and read from the right and used small font size and stamped before the paint.
Much later:
Here is a 04-75 metric MKIII small font stamped plate still mounted on right, but later ones read from the left.
SN/VIN and frame # do not match.
MKIIImetric.jpg

Here is the 05-75 imperial tube MKIII frame .
Cert plate on left, font read from right, which is opposite from early models.
Frame # stamped over paint, rusty frame # digits on neck. This is when the SN/VIN and the frame # start to match!!!
MKIIIimp.jpg

So far.......... the sequential mixed use of metric or imperial frames seem to be quite random from late 73 until the end. But I am not aware of it being researched or the real norton factory disclosing the data

My rusty frame number information post #21 above is backwards-sorry
 
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Imperial frames back bone 2,25"+paint/ 57.45mm and narrow rear loop

Metric frames back bone 60mm/ 2.36" and wide rear loop

my observation of the cert plate mounting location trend is:
imperial plate on left/drive side
metric plate in right/timing side
plate rotation varies with era
YRMV
 

MichaelB

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Of course one can never be certain of anything Norton.
Mine is 74 Mk 2, Sep 73 build
Metric Wide loop
Cert on Left/drive side.
Small numbers for the VIN, larger for the date.

Once I decipher the frame number, I'll submit it for your web site.
 
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myron1950

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Original label and installation prior to removal for frame PC.
1974 Roadster, build date (per label) 10, 1973
#308719

Note orientation relative to head stock features
 

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Time Warp

.......back to the 70's.
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Original label and installation prior to removal for frame PC.
1974 Roadster, build date (per label) 10, 1973
#308719

Note orientation relative to head stock features

Do we assume that is an imperial frame.
I have the same data plate (that AN do not reproduce) stamped 12/73 and Mk2a/metric frame as per the Page 1 pic but read from the D/S but mounted more to the T/S.
Both seem to line up one side of the steering lock plate so perhaps some form of drilling jig was used that could be lined up either side.
Maybe Rodney Dangerfield's English cousin did the drilling.
 
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early 850
*300971 4-73
*Metric-wide loop
*cert on RH side
*no frame batch # but "00103" on left
*NO PN on LH tank mount
 

NickZ

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Dave,
Didnt understand what you were getting at to start with.
I guess I thought that the simpler the question the more likelihood of people responding.
But you make a worthwhile point.
Soooo.... Survey Mark 2

The following info would give a more detailed picture.

1. Which Plate do you have (see pic that follows)
2. Date on plate as it is written on the plate
3. Orientation of the plate. Which way up is the printed writing, correct viewed from primary (LHS) or from timing side (RHS)
4. Is stamped number the same way up as printing
5 Is date stamping the same way up as the printing
6. 750 or 850


Deep breath.....reply now...
149xxx: 1971 Roadster with original label.
1. 06-1441
2. JUL 1971
3. RHS Timing side
4. Yes
5. No
6. 750

151xxx: looks like original label, but don't know history.
1. 06-1441
2. SEP 1971
3. RHS Timing side
4. Yes
5. No
6. 750
 

gortnipper

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1. 06.3247
2. 4/74
3. correct viewed from timing side (RHS)
4. Is stamped number the same way up as printing - yes
5 Is date stamping the same way up as the printing - yes
6. 850
Metric frame, with plate mounted more to the drive side, per other's pics
 
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Certainly plausible. Two data points that might slightly modify.

1) I have a label that I believe to be original that has the serial number (203143) stamped readable in the same direction as the printed label and the stamp is deep enough that it is doubtful that it was done on the frame. The date is stamped upside down and not deep at all. Also, it is stamped "1972 Jan". I have been guessing that , at least at that time, that the label was stamped with the serial number and then it was installed on the frame. The date was later stamped.

2) If you zoom into the picture here: https://andover-norton.co.uk/en/service/ you'll see that the label is already on the frame and the steering bearings are installed. That's a weak data point, but something to consider nonetheless.

The label is 06.3247 (according to AN)

Based on my research - and assumptions, I concluded that the ID number was stamped prior to fitment, and the date stamp was applied after build. I could further speculate that the date stamp was only applied immediately prior to dispatch. It's the only way I can figure as to why there's so much inconsistency when trying to pin down a build date, and why the date stampings are often pretty much all over the place - or just not present at all.
 
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Based on my research - and assumptions, I concluded that the ID number was stamped prior to fitment, and the date stamp was applied after build. I could further speculate that the date stamp was only applied immediately prior to dispatch. It's the only way I can figure as to why there's so much inconsistency when trying to pin down a build date, and why the date stampings are often pretty much all over the place - or just not present at all.
I think this must be right. My 72 Interpol has no date stamp. I have checked with NOC, AN and VMCC and all of them have no dates recorded for mine or a whole batch of Interpols around my number.
I figure that a batch of bikes were built as Interpols and moved into a separate area for final build and the date was never recorded or stamped At the time of despatch. Mine is an early 200xxx, which should be a January build, but was not registered by the Police until August.
 
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When I worked at Longbridge the VIN plate was stamped as the body dropped down onto the start of the assembly line, 8 hrs later it came off the assembly line and then normally took another shift before passing to sales where it then waited in a car park. When it was loaded onto a transporter it was recorded as despatched.

For 90% of vehicles this resulted in the start assembly/finish assembly/passing to sales and despatch happening within a week. But the last 10% could be held up anywhere, a significant proportion were rejected as they came off assembly and could spend weeks being repaired. There was one guy employed as a chaser, he drove around the plant chasing up the aging cars and trying to get the repairs prioritised so the oldest were done first. Can't see that Norton were any different hence the dates being all over the place.
 

marshg246

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Based on my research - and assumptions, I concluded that the ID number was stamped prior to fitment, and the date stamp was applied after build. I could further speculate that the date stamp was only applied immediately prior to dispatch. It's the only way I can figure as to why there's so much inconsistency when trying to pin down a build date, and why the date stampings are often pretty much all over the place - or just not present at all.
That's what I think as well - at least for some years.

I get many visitors a day to my Commando Survey, but only once in a while a submission. Eventually I hope to have enough info to be sure about that and a few other things.

Based on the dispatch records I've seen, I suspect that Norton changed the way they did things over time - they certainly were slowly modernizing the dispatch records.

For anyone who doesn't know about the survey data, it's here: https://www.gregmarsh.com/MC/Norton/CommandoSurvey.aspx
 
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