Specs Motorcycle

I had made a post of a NORTON 650SS restoration or so that was what I thought. Today I got some mails from Mr. Gary Parker who is the Canadian representative for the International Norton Owners Association stating that the mentioned bike is actually a Norton Atlas 750. He had justified his statement through his mails. When a person of his stature has confirmed about the Norton, than I guess, we can rest all doubts about the model. I got quite a few mails with the queries surrounding the mystery of the bike. I guess the following mail from Mr. Gary Parker will rests
all doubts.

Hello there, My name is Gary J Parker, and I am the Canadian representative for the International Norton Owners Association. The bike in the photos that are posted on the "Visual Gratififcation" blog are of a Norton Atlas 750. They are NOT from a 650SS or a Commando. There are a number of ways we can identify this.
1) The engine breather on an Atlas (and very early Commandos) exits the engine on the front drive side, off the end of the camshaft, whereas the 650SS engine breather exits the engine at the REAR of the drive side crankcase. As you can see from the photo of the drive side, there is an angled pipe on the front drive side which eliminates the possibility that this engine is a 650. That area would be bare if this was a 650 engine. The pipe is almost uniquely Atlas.
2) Commando top end oil feed is from the sides of the head, between the rocker spindle cover plates, google any image of a Commando and you will see the oil feed in the space between the spindle covers, whereas the Atlas has its oil feed from the top of the head, on either side of the head steady. On your engine, the area between the spindle cover plates is bare, indicating that the head at least is not a Commando head.
3) Your engine has a tach drive, which only the very earliest Commandos were fitted with. 4) Interestingly, your bike is equipped with a "Laid down" Norton gearbox, a design which was changed in 1956, all later Norton twins were equipped with the AMC gearbox, which continued till the Commando. For reference, there were no 650 or 750 motors being built by Norton in 1956. This box is from a much earlier bike.
5) Another interesting thing is the cylinder block, whch is not stock Norton, the fins are too few and spaced too far apart. This cylinder block is in all likelihood a Dunstall kit, bored out to 810 cc. It is DEFINITELY NOT Norton, but aftermarket and desirable. Paul Dunstall marketed "Go Fast" goodies and tuning kits back in the late sixties and early seventies.
Any more questions i would be happy to answer.
cheers, Gary J Parker,
Canadian Rep,
INOA Victoria BC Canada

Well, I also thought that it may be a Commando, but Gary has very clearly put that it is not. He sent some more proof in his second mail.

More: Looking again at the pics, i have come to some conclusions. This bike was originally an early to mid fifties Norton Dominator or single, in all likelihood a bike which had a catastrophic engine failure. The frame and all cycle parts are too early to be Atlas (Or 650SS for that matter)
the frame number (Located on the metal flange which is directly behind the primary chaincase) will tell a great deal but the frame is quite early, I would say 53-55, and may even be from an International or Manx OHC single. It is definitely "Wideline" or pre -1960.
My conclusion, a long time ago someone with a wideline Dommie or Inter blew their engine up and found a mid sixties Atlas with a Dunstall big bore kit and plumbed it in.
cheers, Gary
PS search for frame numbers and engine number is on front drive side of crankcase just below barrels.
I am very familair with the Norton Dominator/Atlas/650SS/Mercury series of bikes, I own two and have restored a couple more.
cheers, Gary

I recieved another mail from him with his final thoughts.

OK, More conclusions. Sometimes it takes quite a few looks to get familiar with something. Some things are obvious, some things must be inferred by context and "Feel".
Engine: 750 Atlas engine, 1963-68, fitted with Dunstall overbore kit, possibly 810cc. will be stamped thus: 20 xxxxxx or something along those lines, followed by the letter "P". Possibly stamped N15CS xxxxxx (xxxxxx indicates actual serial number) If the latter is the case, then the engine, while identical to an Atlas, came from a Matchless/Norton hybrid scrambler, made between 65 and 68.
Gearbox: pre 57 "Laid down" Norton box, 4 speed. Carburetion: Wal Phillips Fuel Injectors, rare nowadays, period aftermarket "Go Fast" goody commonly used in the sixties, difficult to find now.
Frame; Looking more and more like a Manx or Inter OHC single frame, the key is the curve to the rear of the engine, the twin frames had a tighter bend, frame number if found will tell. Definitely pre -1960 which eliminates as noted any likelihood of it being a 650SS. This baby is a true "Bitza". Frame number, as previously noted, will be found on the flange to the rear of the primary thus: 122 or 14 or something like that, the 122 if present would indicate a Domi 88 500cc, the 14 indicates a Domi 99 600cc. These are model deignations, the actual serial numbers follow. If the frame is a true Inter or Manx, instead of 122 or 14, the horizontal number will be either 10, 10M2, 11 or 11M2. Let me know what you find, Im curious. The frame, although early, is not TOO early, being post 54 as the rear section was bolted on prior to that, not welded as in this case. The shocks are Armstrong, not Girling, so mid fifties is what Im thinking. the rear brake has been heavily altered and may not be Norton at all, it has a bolt on sprocket, which Norton roadsters didnt have at the time. the front wheel (Or at least the hub) is conical, possibly Manx, but there is also the possibility it might be late Triumph, but Im betting on Manx or International. The front guard is Inter or manx pattern.
My conclusion then, the bike was a racing Inter or even a Manx (again, without numbers its very difficult), the engine blew or was removed for some reason, and a modified Atlas engine was installed in its place, complete with the Wal Philips rig.
you have a very interesting and unusual bike here, rather a bitza but a good one. Incidentally, the bike in the background in the picture of the timing side is a 57-59 Dominator i think but it isnt clear enough to tell.
cheers, Gary

The third letter had me dumbfounded. There was no question of doubt even after the first letter, but the second and the third... the third was actually too technical and a lot of things flew over my head. I read it thrice, still... I could only capture some ideas what Gary was saying. And I am sure lots of us will feel the same.
This man is a genius on Nortons, what an amazing amazing techno person. Any person on earth having any doubts on his Norton can mail him at atlas65@shaw.ca and I bet even if you have a mudguard from a Norton, Gary will be able to recognize the model!
Thank You Gary, you are amazing... REALLY!

I said "Your engine has a tach drive, which only the very earliest Commandos were fitted with." which of course is incorrect, both the Atlas and some very early Commandos had tach drives mounted on the TIMING COVER, but all later Commandos had tach drives on the front of the crankcases , running off a worm gear located on the camshaft.I also said "The front guard is Inter or manx pattern.", which is misleading, the guard is Manx pattern, Inter guards were totally different, very much like Dominator guards, the International being a roadster, whereas the one in the picture is a racing mudguard, absolutely purebred Manx, not Inter. The bike in question, with a few more looks, is definitely a Manx framed ex racebike, the final clue is in the thin pipe which leads from the upper drive side frame rail to the primary chaincase. This is a chain oiler, with a reservoir in the upper drive side frame rail, a feature which I have only seen in one other place, on a genuine Manx Norton race bike which I featured in an article a while back in the "Norton News". These chain oilers were not installed in roadsters at all, and were unique to the full race spec Manx OHC bikes. You have a RARE frame. The frame used Reynolds tubing, rather than the plain mild steel of the roadsters. This feature does make them a wee bit fragile though when put into service on public roads with hard use. Caution should be exercised, these were seven lap frames, upon completion of which the bike would be thoroughly stripped for inspection and overhaul. the frames are lighter and the tubing thinner walled. The front brake is still a mystery, it doesnt seem to be a stock Manx Norton brake, it isnt a Gramicci or Fontana, and I dont think its a John Tickle either, which leaves me stumped, I am going to keep looking for pics of this particular brakeplate, but it is an odd one I havent seen before.I am a bit envious, the bike is certainly not as it left the factory, but it has obviously a fascinating history and could probably tell some neat stories if it was able to speak. Whoever built it, once the "Cammy" engine was removed, used quality components and took care with the build. The Wal Phillips injectors, the Dunstall barrels make it rather special but any Norton that once was a Manx is interesting enough.

cheers, Gary

PS: Ive owned Nortons for nine years now, so no expert credentials, Ill leave that to the people whove owned and worked on them since before I was born, and theres quite a number of those! I do, however, get pretty obsessive about my hobbies and there is a lot to research to keep me occupied in Norton land and Im learning all the time.

PPS: Please keep me posted and I am VERY curious about frame and engine numbers, if any can be found. This will be the final link in this puzzle.

Norton Atlas 750 and The Bike I posted earlier