I am looking to buy my first Commando and have settled on the 850 Mk1 or 2 and believe I know what the differences between the two are, or rather were when built, a different airbox, exhaust system, and carb. setup.
Have I missed anything out, like engine or gearboxinternals?
Also, over time I guess the differences are less relevant as previous owners have changed these parts to suit.
Any comments would be appreciated.
I think there was a Mk 2 a…
- Log in to post comments
The various 850 marks cons…
The various 850 marks consisted of 1 , 1A , 2 , 2A and 3.
The first 850 , the Mk 1 , came out in early '73 and was a pre "noise control" model with peashooter silencers and paper element air filter - mostly just a Mk 5 750 with an 850 engine.
The first Mk 1A came outof the factory in September '73 and was the first "noise control" model with black cap "bean can" silencers , balanced exhaust pipesandspecial air box withoiled foam air filter element. I've got a genuine Mk 1Awith correct Sept '73date stamped on the steering head plate butwhose engine number is 140 numbers before the official first Mk 1A number according to the Norton records -specialist Norton books refer to engine numbers not being a foolproof model / dating guide as waitingengines wereoften takenout of sequence on the production line.
The Mk 2 , as far as I can tell from research, was a special production batch for export to USA only with some particular mods specifiedfor the States' market.It's possible some found their way onto the UK market. Maybe somebodyhas further info on theMk 2.
The Mk 2A , which was produced in large numbers from early'74 to '75, was similar to the Mk 1Aandthe last pre-electic start 850. Amongst a few other small cosmetic changes ithad a different style chrome chainguard and I believe metal battery side panel instead of the fibreglass onefitted to the Mk 1A. Alsoa cylinder head mod (there were about 10different cylinderheads available for the 850 developed during its manufacturing lifetime , '73 to '77).
The Mk 3 , launched in '75 ,is a very different bike fromearlier Commandos with theelectric start arrangement ,gear lever change over to the left side , radically changedand more complex primary drive side , front disc over to the left fork leg , andrear disc brake.
There area fewexcellent specialist books on Commandos (eg , Super Profile , Buying a Commando , etc)which can give you very precise info on the differences between the Marks with engine / frame numbers , etc , plus enlightened comments from authors who really know the subject.
- Log in to post comments
I think there was a Mk 2 and a Mk 2A. The Mk 2A had the air cleaner which was later used on the Mk 3, and also the same swinging arm spindle as the Mk 3. Very confusing to me when I had a Mk 2A and tried to repair it after reading a Haynes manual.