1972 Norton

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My understanding is that Norton made both Combat and non-Combat models during the period.
One external way to know for sure is the 'C' stamp on the head (not easy to find).
 
Sounds like a possibly earlier model. The stamped "C" on my Crazy Combat was found under the head steady support but I've seen the "C" stamped closer forward towards the exhaust rocker covers too. If it has the thin type pressed steel headsteady you could pullthe tank and allen key out the 3 screws to lift and take a look. If you intend to ride the bike you will be getting a better headsteady anyways as those break. Another thing to look for would be the distance between the head and the top of the iron barrels. It would be a distance that is smaller than other models as they shaved the head to achieve a higher compression. Crankcase breather would be down low at the rear of the engine with a large hose leading back to the oiltank. If it comes out of the front left of the crankcase it could be an earlier model . So look for these differences.
 
200976 was the official start of Combat production, however Commandos with earlier numbers apparently built to Combat specification do appear to exist.


Torontonian said:
Crankcase breather would be down low at the rear of the engine with a large hose leading back to the oiltank. If it comes out of the front left of the crankcase it could be an earlier model.
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Any 200000-on 750 Commando should have that breather-and it's presence doesn't necessarily identify a Combat.
 
Whether built at the factory or by the owner a combat spec can easily by done on any 750 with '72-'73 crankcases. A previous owner changed the cam in mine to the standard which in my mind made it no longer a combat. I fixed that. My point is over the decades original machines get changed. If the machine you're considering has been done at the factory or altered to combat spec, it's a combat.
 
Any 200000 and up is the combat "breather", but the earliest combat "tune" I have worked on (in 1989) was 200205*, so IMO the quoted list is not correct. I was very observant of the hardware and lock washer markings and known history of the machine and am confident it was original factory combat tune.

*Edited by the moderator as dynodave subsequently discovered the number to be 202005.
 
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What makes Combat spec is shaved .040" head for 10-ish CR and the 2S cam to pack mix in better than lessor engines can. I asked same thing on 3 major lists in '99 wondering if my 1st Combat really was and told easiest-fastest way was to see if it tended to hesitate an instant accelerating d/t rear tire spin chirping noise on WOT snicks to 2nd and to lift front finishing 1st and 2nd into red line zone. If non-C marked small port head was shaved and installed with 2S cam then should also lift front finishing 3rd gear with 19 or 20T sprocket. If really a Combat operated in 2S zone then should also find clutch basket wobble as hot rod lower gear use will have worn the snot out of dry spun sleeve bushes. Oh yeah real Combat spec can not tolerate much full spark advance over 28' w/o mean back fire kick starts so another way to know - if was tuned properly.
 
Look for a combo of the things mentioned. Breather, fin distance, "C" stamp, and a front disc brake. It's a lot to try and replicate if it's not a real Combat, and if it has all of them and the patina looks like it has not been touched in a long time you probably have a Combat. Good luck.


Scott
 
kernel65 said:
and the patina looks like it has not been touched in a long time you probably have a Combat. Good luck.
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Thats not a terribly good indicator ?
ALL Commandos are now appraoching near 40 years of age, (at least) so plenty could have been done to them
in the intervening years and they'd have that 'untouched for a long time' patina.
 
Rohan said:
kernel65 said:
and the patina looks like it has not been touched in a long time you probably have a Combat. Good luck.
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Thats not a terribly good indicator ?
ALL Commandos are now appraoching near 40 years of age, (at least) so plenty could have been done to them
in the intervening years and they'd have that 'untouched for a long time' patina.
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When you cut off the rest of the sentence it's not.
 
When you add it to the rest of the sentence its not.

If we had a $ for everyone thats come on here with some mods,
and said 'it looks very old and original' .....
Patina alone is simply not a reliable indicator for something mechanical thats pushing 40+ years old.
 
Non Combat had 30mm Amals L.H. L930/64 R.H. R930.63
Combat had 32mm Amals L.H. L932/18 R.H. R932/19
 
A couple of 'easy indicators' which would offer some clues:

As already said, 32mm carbs are fairly easy to check, plus from a distance the 32mm manifolds have single ribs top and bottom, whereas the 30mm manifolds have triple ribs.
The gap between the barrel & head is smaller, but probably a bit subjective without being able to compare. That said, it's a very small gap.

For deeper investigation, the standard pushrods send the valvetrain geometry out of kilter and the tappets don't rest on the centre of the valves, but a lot will have had these done by now - I think mine needed .060"-.080" off to restore some kind of symmetry, i.e., more than the .040" shaved off the head.

1972 Norton
 
NjNortonCommando said:
Can anybody confirm or deny this? I am looking to buy a 1972 Commando and the guy keeps tellin me it is a combat but the vin is 200581.
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If he keeps telling it's a Combat I'd use this as a very good reason for a price cut - based on the work need to rectify all the lousy Combat gremlins they installed back then .... :twisted:


Tim
 
1972 Combat ,cases have no engine number stamped and the carb is a single SU. Head stamped C under steady and engine contained a 2s cam narrow gap between head and barrels and breather at rear of cases, but it was the air horns that gave it away!

J
1972 Norton
 
I had 'crash' bars just like that on my 1973 Interstate back in the day. Wassell brand from England I think.

During a slow speed lay down the bars will protect the rider a bit, but they can bend/twist the frame down tubes and the clamps will put a flat dent in the tubes.
 
rx7171 said:
Non Combat had 30mm Amals L.H. L930/64 R.H. R930.63
Combat had 32mm Amals L.H. L932/18 R.H. R932/19
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Actually it's 19 & 20 on the original Amals.
 
illf8ed said:
rx7171 said:
Non Combat had 30mm Amals L.H. L930/64 R.H. R930.63
Combat had 32mm Amals L.H. L932/18 R.H. R932/19
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Actually it's 19 & 20 on the original Amals.
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My Norton Villiers 750 Commando Parts List book has them as 18 and 19 specifically noted for the Combat.
Publication No. 063402 Printed in England Parts Group 9 Parts #062709 and #062710
Is there a possibility you are looking at 32 mm Amals not for Combat, although the 19 appears in both our number set.
 
Tintin said:
If he keeps telling it's a Combat I'd use this as a very good reason for a price cut - based on the work need to rectify all the lousy Combat gremlins they installed back then .... :twisted:


Tim
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Provocative ;)
But true. If the case mods haven't been done it could be a big gamble, and should be factored in.
That said, it's well worth the effort - my Combat was much more fun to ride than my 850
 
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