What Mark Am I? (2011)

I have a 1973-750 with a January 1973 production date, the SN is 220406. Originally equipped with twin 932 Amals. I often see "Mark" numbers reffered to and wonder which one mine is, what does it mean, and why should it matter.

Thanks in advance.

Steve

On my number list it is a MK V. Don't know why or what it means or if it matters.

Dave
69S

It gets wierd(er)... Mark III was the LAST model produced...

grandpaul said:

It gets wierd(er)... Mark III was the LAST model produced...

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Yes, but that was for 850's.

The 750's had more versions, they got to the Mk V.

grandpaul said:

It gets wierd(er)... Mark III was the LAST model produced...

Click to expand...

There are separate "Mark" numbers for the 750 and 850 models. According to Roy Bacon's book, the 750 models went up through (IIRC) Mark V, although it's very rare to hear anyone refer to Mark numbers on a 750.

Debby

steveyacht said:

I often see "Mark" numbers reffered to and wonder which one mine is, what does it mean, and why should it matter.

Click to expand...

= 750 MkV

The Norton factory updated the Commando model range (or introduced new models) in a rather haphazard manner and this did not occur at regular 12 month intervals, so a particular Commando cannot really be identified accurately by 'year model' but can be identified by its variant specification or 'mark number'.




750cc
Original Commando 4/68-3/69
750 R 3/69-9/69
750S 3/69-6/70
Fastback 3/69-8/70
Fastback II 9/70-12/70
Fastback III 1/71-12/71
Fastback IV 1/72-3/73
Fastback LR (Long Range) 4/71-12/71
Fastback LR MkIV 1/72-2/73
Roadster 3/70-12/70
Roadster II 1/71-12/71
(there were no MkIII Roadsters, apparently!)
Roadster IV 1/72-2/73
Roadster V 3/73-10/73
SS (Street Scrambler) 3/71-10/71
PR (Production Racer) 4/71-10/73
Hi-Rider 5/71-12/71
Hi-Rider IV 1/72-2/73
Hi-Rider V 3/73-10/73
Interstate 1/72-2/73
Interstate V 3/73-10/73

850cc
Roadster 1 4/73-12/73
Roadster 1A 9/73-2/75 (I think that should be 2/74)
Roadster 2/2A 1/74-2/75
Roadster 3 2/75-9/77
Interstate 1 4/73-12/73
Interstate 1A 9/73-2/75 (2/74?)
Interstate 2/2A 1/74-2/75
Interstate 3 2/75-9/77
Hi-Rider 1 4/73-12/73
Hi-Rider 2 1/74-2/75
Hi-Rider 3 3/75-?
John Player Replica 11/73-2/75

(Some US 750 'MkV' spec. Commandos appear to have been built before 3/73)

Hi L.A.B.

Roadster MkIV if defined as with crankcase breather at the bottom rear of the drive side crankcase and elimination of the sump filter, aka combat engine, I would have to comment from ownership of these models the prodution start was before Jan '72. I know below figures are what Roy Bacon publishes. Also know from copies of factory build records there was an overlap of production during the last three months of '71 where both '71 spec and '72 spec were being assembled at the same time. Doesn't pay to get too exact on these details.

Roadster II 1/71-12/71
(there were no MkIII Roadsters, apparently!)
Roadster IV 1/72-2/73
Roadster V 3/73-10/73

It is indeed a complicated business with the 750 Mk numbers.

Generally though, most owners and dealers will refer to the 1972 model year bikes starting at 200000 as MkIVs - these have the breather at the back and the steel blanking plate on the rear of the timing chest. Cycle parts included short alloy clock holders and the earlier pattern tail light.

MkV is generally used for the 1973 model year. Breather remained at the rear but the timing chest no longer had a blanking plate. They had square rear lights and long black clockholders, like the 850s.

It's rare to see the 'Mk' terminology applied to the 20M3 or 20M3S motors with the camshaft breathers.

The MkV 750 was the last in the 750 series and has the strongest cases of the 750's and came with the 5-plate clutch as well as a hi (RH6) or lo (RH5) compression head with 932 carbs. Kind of a slightly de-tuned Combat with standard cam and superblends. The bike also had the deep instrument cups (some had Veglia instruments) like an 850 and a large taillight (again like the 850's). The books show they were built from 3/73 - 10/73, but my two both have Nov. 1972 build dates.

You have to wonder how model numbers come about. Like the new Porsche 911, model 991, which succeeds the 911, model 997. I read that 998 is copyrighted by Ducati . Did Lincoln or Norton copyright the MK designations ?

Jaguar has had more than a few Mk models too. ?
Doubt if anyone patented or copyrighted it...

Didn't Ford defend the F150 against Ferrari recently.

Ron L said:

The MkV 750 was the last in the 750 series and has the strongest cases of the 750's and came with the 5-plate clutch as well as a hi (RH6) or lo (RH5) compression head with 932 carbs. Kind of a slightly de-tuned Combat with standard cam and superblends. The bike also had the deep instrument cups (some had Veglia instruments) like an 850 and a large taillight (again like the 850's). The books show they were built from 3/73 - 10/73, but my two both have Nov. 1972 build dates.

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My 750 Has the 932 Carbs, Deep instrument cups, large tail light, Crankcase vent on back of engine, no blanking plate on timing chest and runs stronger than it should. I suppose It has a better than even chance of being a MKV ......... Now I can puff out my chest, hook my bib overall suspenders with my thumbs, and say with pride, "Yup, dat dare is a Mark Five, by gosh!" When I get asked what she is. :mrgreen:

The use of "Mk" or "Mark" probably stems from British Army terminology where it has been common for more than a hundred years to find references to things like "No.2 Mk 5 Series 1 " for the various progressions. I think that we can blame the V.A.O.S. (Vocabulary of Army Ordnance Spares).

In Belgium, they insist on calling Mk.IIIs 'Emmkars" and this can also be heard with vehicles like Triumph Spitfires. The only proper Spitfires, of course are the 'Emmkars'.

Sorry about the necroposting, but the whole idea of "Mk" variants for 750s is a nonsense. If you're going to call the Combat series (strengthened cases, official kick-off 1st of January, 1972 but some "pre-production" motorcycles down the production line at the end of 1971) 750 a MkIV but leave out the Mk III, there's no way to differentiate the earlier ones without calling a MkII Roadster with the same wiring harness as a MkIII Fastback as different specification.
Just forget the "Mk" business and specify a motorcycle for spares or model description by date of manufacture and serial number.

That was the point of my attempted thread where I posted my same conclusion as yours.
Simple frame version differences
Simple drive train variants
Simple named body styles to match or complement the particular frame /drive train variants

https://www.accessnorton.com/NortonCommando/versions-of-commando.27393/#post-413511

Keeping minds voluntarily following a train of though is like herding a bunch of meerkats. LOL
So I gave up the completion on this forum and will try and refine this thought process and offer it to Barry for the INOA newsletter as well as put it on my site.

“Simple named body styles to match or complement the particular frame /drive train variants“
Regarding this....was the frame the same or different for ‘69-‘70 S and roadster as for fastback. I only have experience with the central oil tank versions, but since the tank is mounted to the battery tray likely the frames were the same.

The 68-70 S1 frames are all the same except for the widow maker.
The S1 oil tanks, S/central and fastback, are the two options and were original to the S1 only but obviously matched the body work.
Yes They each had their own matching battery/tank tray,

dynodave said:

The 68-70 S1 frames are all the same except for the widow maker.
The S1 oil tanks, S/central and fastback, are the two options and were original to the S1 only but obviously matched the body work.
Yes They each had their own matching battery/tank tray,

Click to expand...

Right. For 71, the tyre pump pins were deleted from the frame (not a functional change) and the side and centre stands were altered which required changes to the fitting points for each. Except for these non-important changes, the frames were unaltered between the widowmaker and the 850 with the change for the front suspension rake angle (a major, functional change).