RH 4 or RH10

L.A.B. said:

Well, no, it doesn't, as the date on the registration document is only proof of when the vehicle was first registered, no evidence of build date whatsoever.

For instance, according to the certification plate date stamp, my MkIII Commando was built in 7/75 but it wasn't registered until 11 months later. My T160 wasn't registered until nearly two years after its build date.

Click to expand...

Wouldn't you agree that it is indicative of a later build date as a bit unlikely it sat around in stock for 18 months at the height of 750 popularity - over 50% longer than your T160? Being of a certain age, I remember MkIIIs and certainly the white/yellow TT160s were starting to get fairly sale-proof near the end.

A certain "L.A.B" wrote

L.A.B. said:

Ah no, you have clearly misunderstood something or come to the wrong conclusion. A "P" suffix attached to a Norton engine number may indicate the engine was built at Plumstead (AMC works). A "P" marking on a camshaft simply denotes that it is a standard Commando camshaft.

Click to expand...

Photo isn't of an engine number with a P suffix and Plumstead closed in July 1969. Could you give me a reference for a P-marked camshaft, please?

Oh, and re: the 750 remark - a certain "dillinghamp" was adamant it was a 1971 model 750.
"I'll continue to back dealer replacement cock up with an 850 engine into a late 71MY 750", given the alloy clock cases, unbalanced 750 exhaust system and the frame number, it sure still looks like a late 71MY 750 that's had a 850 engine, a rear light, switchgear and some black instruments fitted in the wrong casings. If indeed, it is an 850 frame, then perhaps it's an 850 that's been backdated....

Girls, please, with the various threads, I am trying to have a fact-based discussion leading to a theory that fits the known data. It with then be possible to test that data against further data other members may be able to provide, again NOC and VMCC records, and with surviving Andover/Wolverhampton employees. We may then be able to arrive at the truth, perhaps?

"when you have eliminated the impossible, whatever remains, however improbable, must be the truth"

dillinghamp said:

L.A.B. said:

Well, no, it doesn't, as the date on the registration document is only proof of when the vehicle was first registered, no evidence of build date whatsoever.

For instance, according to the certification plate date stamp, my MkIII Commando was built in 7/75 but it wasn't registered until 11 months later. My T160 wasn't registered until nearly two years after its build date.

Click to expand...

Wouldn't you agree that it is indicative of a later build date as a bit unlikely it sat around in stock for 18 months at the height of 750 popularity - over 50% longer than your T160? Being of a certain age, I remember MkIIIs and certainly the white/yellow TT160s were starting to get fairly sale-proof near the end.

Click to expand...

Indicative?
Either you know when your Commando was built or you don't? So, no, I wouldn't necessarily agree. And it may surprise you to know that 18 months isn't 50% longer than (almost) 2 years. :? Already "last year's model" by the time it arrived at the dealers, it could have sat around unsold for months.

Still no explanation why the engine is '73 (230233) and the frame, gearbox is '71? I take it you are not its first (second? third? fourth) owner?

dillinghamp said:

Photo isn't of an engine number with a P suffix and Plumstead closed in July 1969.

Click to expand...

Yes I do know what a camshaft looks like, (even though the photo of it is not that good) but I thought I'd better give the full "P" explanation just to reduce the chance of any further misconceptions on your part.

dillinghamp said:

Could you give me a reference for a P-marked camshaft, please?

Click to expand...

061084. Although what the latest AN standard camshaft marking is (if any) I have no idea.

062608 (061084 current AN part number)

dillinghamp said:

Oh, and re: the 750 remark - a certain "dillinghamp" was adamant it was a 1971 model 750.
"I'll continue to back dealer replacement cock up with an 850 engine into a late 71MY 750", given the alloy clock cases, unbalanced 750 exhaust system and the frame number, it sure still looks like a late 71MY 750 that's had a 850 engine, a rear light, switchgear and some black instruments fitted in the wrong casings. If indeed, it is an 850 frame, then perhaps it's an 850 that's been backdated....

Click to expand...

Oh lordy! :roll:

It's a '71 750, then it's a '73 850, and now its back to being a '71 750 again.

Apologies - I mean't 50% longer than your MkIII, but I expect you realised that.

Yes, I have a camshaft with a P on it too. I know 06-1084 is a standard camshaft, but actually there are two standard camshafts. The one you have in your picture is actually 06-1084. 06-2608 has plain, rather than scrolled, bearing areas for the bushes. I refer you to Norton Service Release N77 Feb 1972. "New type camshaft bushes with oil grooves are introduced for 1972. To suit these, camshafts are being produced without the figure of eight oil groove which was a feature of previous camshafts. Whilst we will continue to stock the bushes and camshafts of the previous type for spares purposes, all concerned are alerted to the danger of using a 1972 non-grooved camshaft in pre-1972 non-grooved bushes, which could result in oil starvation and possible engine damage. 1972 camshaft bushes are of a smaller outside diameter than previous camshaft bushes and as a result, it is not possible to fit later bushes to an earlier crankcase. No harm would result from using a grooved bush if this should prove necessary at anytime". Also to Service Release Number N3/13, which provides part number and interchangablility information. Since scrolled cams work with either plain or scrolled bushes "Scrolled condition camshafts only will be supplied against orders..."

Yes, bike could have sat around for months, but we're talking a year and half here, when Norton was knocking out up to 12k a year. But then this discussion is not about my bike. I provided some details about my bike for the benefit of the discussion. You are starting to come across to me as though you want to know about my bike purely to criticise, rather than enable the discussion, which I'm sure isn't the case. Suffice it to say, I know almost all of the history of my bike and have owned it for a very long time.

dillinghamp said:

Apologies - I mean't 50% longer than your MkIII, but I expect you realised that.

Click to expand...

To be honest, I don't know what to believe.

dillinghamp said:

I know 06-1084 is a standard camshaft, but actually there are two standard camshafts. The one you have in your picture is actually 06-1084. 06-2608 has plain, rather than scrolled, bearing areas for the bushes. I refer you to Norton Service Release N77 Feb 1972. "New type camshaft bushes with oil grooves are introduced for 1972. To suit these, camshafts are being produced without the figure of eight oil groove which was a feature of previous camshafts.

Click to expand...

Yes, it possibly is 06-1084 only.
However, 06-2608 only appears in the 850 MkIII parts list, and the MkIII had unscrolled cam bushes
http://www.nortonmotors.de/ANIL/Norton% ... 01&Part=16

http://www.norton-parts.com/a-14143545/ ... for-850cc/

http://norvilmotorcycles.co.uk/
061084

062608

dillinghamp said:

Yes, bike could have sat around for months, but we're talking a year and half here, when Norton was knocking out up to 12k a year. But then this discussion is not about my bike. I provided some details about my bike for the benefit of the discussion. You are starting to come across to me as though you want to know about my bike purely to criticise, rather than enable the discussion, which I'm sure isn't the case. Suffice it to say, I know almost all of the history of my bike and have owned it for a very long time.

Click to expand...

Yes, you seemed happy enough to offer information about your bike, until some pertinent questions were asked about its provenance (not just by me I hasten to add).
The V5 registration information was of course a total red herring as I'm sure you know.

Questions were asked out of curiosity. Considering you are under the impression the bike was, perhaps built somewhat later than the serial number would suggest, it should only need a swift look at the certification plate to put an end to the apparent mystery of when it was built (+ or - a month or so, probably) however, your sudden reluctance to continue this discussion can only lead one to assume that either the certification plate isn't date stamped, or it isn't there, however of course don't feel that you are under any obligation whatsoever to set the record straight.

This is a very interesting thread that makes me wonder just how common bogus engine numbers are. Of the ones I know/have/had there were two pre-Commando that both were legit, however out of 5 Commandos 3 were questionable at best. In one case, a guy was trying to sell me an '850' that while the number was marked as an 850 it was clownishly stamped on a clearly 750 motor. And he was pissed off when I pointed this out! Whoa!
So the thoughts for the day: How many numbers turn up false and what are our liabilities when we run into (purchase or inherit) one? Is this more of a problem with Commando's than pre's?

Just thinkin...

Oh, sorry, yes, Norton Villiers replaced the engine under warranty with a, then, brand new last of current production Mk5 750 unit. Very quick. I split the barrel in 1982 on the M6, at the front, round the base flange, while I was working for Bernard Hooper. On the Monday morning, he said "where's the Commando"? I told him. "Leave it with me", he said. Two hours later, David Sankey (of GKN Sankey, who'd acquired the Marston Road site) arrived in his white E-type, opened the boot and handed over an almost brand new 750 barrel. "It's only done a few hours on development. It was holding a door open", explained Bernard. Happy days.

This may help too...
126125 First Commando
128646 New type sleeve gear and layshaft pinion tooth form.
129897 Rear wheel security bolt.
129897 MK2 type frame
130979 Apex oil control ring
131257 Engine pre-fix 20M3S. Points in timing cover, internal rpm drive, fastback, S type and
roadster.
132576 Fibre clutch friction plates.
133488 3rd gears in stronger material.
134108 First engine built in Wolverhampton works, all engine suffix P built at Plumstead
Matchless London
134738 Hylomar Rolls Royce sealing compound.
136618 Starter motor blanking plate fitted original starter to fit in old magneto recess.
140061 Plastic rocker feed pipe.
141783 New style. Non adjustable tyre with 4:10 front tyre, Lucas h/bar switches, centre stand on
engine plate was on frame fastback, roadster, SS and high rider, also fastback long range
steel tank.
146584 New type SE oil control ring.
147730 Rear brake drums screwed and riveted.
147846 Toughened kickstart pawl.
148895 Modified inlet valve guide
149670 Oil seal fitted to inlet guide.
150120 Oil pump gasket fitted.
151175 Increased chamfer on tappets to increase oil drain flow.
152000 Rear drum strengthening webs.
152499 Replaceable footpegs.
153150 Riveted clutch back plate.
153324 Tachometer housing gasket.
153362 Chaincase cap o rings.
2000 Breather moved to between gearbox plates on back of crankcase. On left hand end of
camshaft. Engine no pre fix discontinued optional disc brake and combat engine. .
. Fast.back, Roadster, Hi-rider and Interstate.
200004 Commando std cylinder head with increased inlet valve support deleting 2 NM23392
heat insulating - washers oil feed return pipes 612200 commonized to 17".
200708 Tappet locating plate replaces NM12142 to accommodate 1972 combat camshaft.
200976 First combat engine.
201778 Clutch plate scrolled groove.
202116 Four terminal master switch.
202341 Valve spring bottom seat washer thinned to accommodate cylinder head variations to
202666.
202666 Cylinder head amended to accommodate NMT2073 heat insulating washers i.e. reverted
to 060988 -1971.
202760 Revised front brake lever-disc master cylinder.
203136 Front drum brake support plate introduced
203200 Steel gas tank and side covers roadster.
203884 Copper sealing washers under rocker spindle plate bolts.
220000 Black instrument cases, square rear light. Disc brake on all but High Rider. Roadster,
Interstate and high Rider.
300000 850 motor, balanced exhaust system, roadster, interstate and High Rider. All disc brake.
306591 Homologated model for Europe with large black air box and peripheral discharge
silencers. Roadster and Interstate only.
307311 850 motor with black barrel, available as homologated model roadster and interstate only,
called MK2A for Europe. For USA with old type silencers and air filter Roadster,
Interstate and High Rider called MK2.