Useless assorted Norton musings.....

Re: 100+ horsepower Norton 750???

worntorn said:

I believe the 650ss was in production from 62 until 68 with very little change, just a few ancillary items.

Glen

Click to expand...

Wasn't there a year or more production of the Norton 650 Manxman starting somewhere around 1960, 61?

Re: 100+ horsepower Norton 750???

Dances with Shrapnel said:

Wasn't there a year or more production of the Norton 650 Manxman starting somewhere around 1960, 61?

Click to expand...

There were Manxman, 650, 650SS and Mercury models, and also mentions of a Deluxe model. (Were any Deluxe 650's built ?).

And also monobloc and concentric models, 6v and 12v models, and engine heads with and without spiggotted cylinders. And speedo and taco models and speedo in headlamp.
While these all may come under 'ancillaries', if you are looking for a particular year or look, it thins down the choices considerably, its not as though they are all exactly the same.
None of them were made for much more than about 2 consecutive years... ???

And the Atlas models are known as Atlas and Atlas Mk2 models, although I've not seen/ can't recall what actually distinguishes them ??

Re: 100+ horsepower Norton 750???

Thats correct, the Manxman was mechanically virtually the same as the 650ss. The Manxman is quite a different looking bike than the SS, so I didnt include it as part of the model run.

Of course as with most makes and models there were slight updates to the 650 ss along the way, but the overall appearance, mechanical details, character and riding experience of the bike was very little changed from 62 to 68.

I think it would have to be considered a model that was in production for more than " a year or two". If we are going to consider a change in the speedometer type to be akin to ceasing production of a model, then the Norton Commando with all of its variations would have to be viewed in the same way. Using that lens, the Commando, which had wild variations in styling and plenty of mechanical changes too, far more of both than the 650ss, was a model that was only ever produced for a short time.


Glen

Re: 100+ horsepower Norton 750???

worntorn said:

If we are going to consider a change in the speedometer type to be akin to ceasing production of a model, then the Norton Commando with all of its variations would have to be viewed in the same way. Using that lens, the Commando, which had wild variations in styling and plenty of mechanical changes too, was a model that was only ever produced for a short time.

Glen

Click to expand...

I've had several 850 Mk 1 Commandos, and they were ONLY built in 1973.

Granted they are not much different to what came before or after, but as a specific model they were only made for less than a year.
Production numbers were not huge either, if you want exactly that model you'll have to look carefully for one...

Re: 100+ horsepower Norton 750???

It was this statement that didn't sound right to me
" When you look closely, if you went hunting for a particular model of any Norton Dominator, they rarely were in production for longer than a year or 2 at most, before the b-annual styling or engineering changes. Except for the Atlas, which was produced in some volume for some years - although there were a few slight variations of them.That makes any particular dommie model somewhat scarce ?"

As stated, the 650ss was one Dominator Model that ran for six years with very little change, really just updates like the improvement in lighting by going from 6 volt to 12.

The Atlas started production after the 650ss and ceased production before the ss. It also saw more mechanical change than the Ss did. The 650SS was a true sports model from the start to finish with twin carbs, same high compression and the famous SS cam from 62- 68.

According to Mick Walker, as compared with the SS, the original Atlas came with a mild cam, low compression ratio and single carb. This was at Doug Heles direction because he knew the 750 size would create vibration problems. After Hele left Norton, the Atlas Compression ratios were gradually increased to that of the 650 and twin carbs were added. Eventually the Atlas also came with the SS cam too. Hele was correct, the vibration problem got out of hand.

Re: 100+ horsepower Norton 750???

I'm sure you are right. I've not had much to do with 650 models.

But, if you want a 650 model with 12v electrics, speedo and tacho neatly styled, and concentric carbs, then you don't have a choice of many years to choose from. ??
And if you want a blue manxman, likewise not many years to choose from.

So did any Deluxe 650 models appear. ? They are in the parts book...
That rear enclosure looks neat, these days, and that blue and white paint scheme was quite spectacular. But did they make any ?
Bet they make maintenance difficult ?

And the Mercury didn't go for long either ?

Re: 100+ horsepower Norton 750???

Was the Manxman the first of the 650's?

When were the first Norton 650's manufactured (what model) and when did they appear in North America?

Re: 100+ horsepower Norton 750???

Was the Manxman the first of the 650's?

When were the first Norton 650's manufactured (what model) and when did they appear in North America?

Re: 100+ horsepower Norton 750???

Right, the Mercury didnt go for long. I guess for me, I am happy with any model year of 650 SS. Unlike Beng, I consider the small changes in the 650 along the years fron 62 to 68 to be improvements, ie 6 volt to 12, magneto to points then eventually to Capacitor discharge, even going from Monoblocks to the lowly Concentric is a change Im OK with. As stated in "Know thy Beast", the Vincent owners bible, the change from the old type 276 to Monoblocks then to Concentrics gave better and better fuel economy along with an improvment in acceleration.
The only real problem with a concentric carb can be fixed by sleeving the slide, then they are a great carb. I have them on four bikes, delorotos on one, Mikunis on another, Bing on yet another and an IRZ on one of the Ossas. The Mikuni bike is a dog to start, the IRZ soso, the Bing and all four Concentric bikes are one or two kickers and run perfectly.

As far as the actual riding experience goes, to my way of thinking, as long as the carbs work well it matters very little what is bolted on there, same with ignition.

Glen

Re: 100+ horsepower Norton 750???

Yes, the Manxman was the first 650. It was an export only model and showed up in the US in 1961. It had Western style bars, a red seat and was blue in colour.
The UK got the 650 the following year as the SS. For its full run of 7 years it retained the same color scheme, black frame, dove grey tank against a nice amount of chrome. I still think it is an oustandingly attractive machine, but I might be a bit biased!


http://s402.photobucket.com/pbwidget.sw ... c9333b.pbw
Glen

Re: 100+ horsepower Norton 750???

worntorn said:

Yes, the Manxman was the first 650. It was an export only model and showed up in the US in 1961. It had Western style bars, a red seat and was blue in colour.
The UK got the 650 the following year as the SS. For its full run of 7 years it retained the same color scheme, black frame, dove grey tank against a nice amount of chrome. I still think it is an oustandingly attractive machine, but I might be a bit biased!


http://s402.photobucket.com/pbwidget.sw ... c9333b.pbw
Glen

Click to expand...

Great looking bike.

So is it fair to say that since the 650 Manxman showed up in the US in 1961 it existed in 1960 although maybe only in manufacturing inventory?

Re: 100+ horsepower Norton 750???

Its likely that there was at least a prototype somewhere by late 1960. The head design came directly from the Doug Hele modified 500 that became the first pushrod twin to lap the IOM at over 100 mph.

A friend and I were talking about this the other day. He has a 1956 99 that he is restoring. The 99 made a little over 30 horsepower. Just 4 years later Norton had the Manxman/650ss engine that, with just 50 cc more, made either 52 or 49 hp, depending on the source.
Most of this extra power came from the Hele downdraught head.

Glen

Re: 100+ horsepower Norton 750???

Nortons claimed 29 hp from the original 500cc iron dominator engine of 1949, with quite low compression and a single 1" carb , so some of those numbers are sounding a bit rubbery somewhere ? Or the 650 really was a quantam leap ahead.....

Re: 100+ horsepower Norton 750???

worntorn said:

eventually to Capacitor discharge,
Glen

Click to expand...

I don't think Nortons had that.

Re: 100+ horsepower Norton 750???

From Mick Walkers book "Norton Dominator" the 1956 597cc model 99 or 77 both had the same engine specs at 31 bhp.
A 61 Manxman ad is reproduced later in the book, it lists bhp as 52.

The Haynes shop manual on Dominators has a section that lists all of the mechanical changes to the Dominator models over the years. In 1968 the 650 got cd ignition. My 68 has the original cd setup on there still. Dont know why it wasnt fitted to the Commandos. In 68 the 650 was sold alongside the new Commando, but in quite low numbers. Im guessing that AMC had still had some 650 engines and other parts to use up. Perhaps it was decided to trial CD ignition in this way on a small volume of machines. CD was quite a new thing in 68, though my 68 Ossa Stilleto had it.

Glen.

Re: 100+ horsepower Norton 750???

Any chance of a pic or 2 of this CDI ignition. ?
Particularly inside it.
Does it look different/much different to the points and coil setup ?

Seen it mentioned in various places, but never any detail of what it actually is.
Or why it wasn't continued.

Still recall seeing under the hood/bonnet of a 3rd party cdi fitted to a 4 wheeled device.
Foggy night, looked like the sparks and lightning show under there !!!
Wow, obviously not enough insulation to contain the voltages.
No wonder they have little stickers warning about heart failure...

Re: 100+ horsepower Norton 750???

Looks to me a lot like the early Boyer, only no Boyer name on anything.
I should email Kirby Rowbotham, he may well have supplied the units to Norton.

Should have that bike on the lift soon, will take a pic.

Glen

Re: 100+ horsepower Norton 750???

worntorn said:

According to Mick Walker, as compared with the SS, the original Atlas came with a mild cam, low compression ratio and single carb. This was at Doug Heles direction because he knew the 750 size would create vibration problems. After Hele left Norton, the Atlas Compression ratios were gradually increased to that of the 650 and twin carbs were added. Eventually the Atlas also came with the SS cam too. Hele was correct, the vibration problem got out of hand.

Click to expand...

Mick Walker either never said any of that, or he was simply wrong.

The Atlas road and scramblers always had 7.5-7.6:1 compression pistons through it's production run, and it always had the same cam as the 650ss. The first year the US models came with a single 376 carb, then the next year they came out with a MkII Atlas with dual carbs. Norton did not go back to a flat-top piston and 650ss compression except for the Commando.

From 1962 onwards Norton used the same cam timing and profile for every street bike right through the end of the Commando production, just altered it for the points and tach drive the Commando had after a spell. The last standard cams were used up in 1961 on the standard model Dominators.

Most 650ss and Atlas models sold in the USA in 1962-3 had the exact same cycle parts, small fuel tank and high bars as the 1961 Manxman bikes, so the only difference in appearance was the color of paint. Beno Rodi who's family had a Norton dealership in the 50s-60s, says the last Blue Manxman bikes their shop got in had black seats and not the red seats the early Manxman came with.

Re: 100+ horsepower Norton 750???

worntorn said:

Its likely that there was at least a prototype somewhere by late 1960. The head design came directly from the Doug Hele modified 500 that became the first pushrod twin to lap the IOM at over 100 mph.Glen

Click to expand...

Berliner took over Norton distribution in 27 Eastern USA states in December 1960 and immediately advertised the 650 Manxman the same month as their new flagship. I had Manxman #48 for years, a friend of my father bought it new in April 1961. Right now I have Manxman #3, which I believe the factory records show was "dispatched" in Nov. 60', I don't know when it got to the US, then to a dealer and was sold though.

I would not say that the 650 head came from the Domiracer, since the Domiracer did not appear in public with that head until several months after the Manxman was running with it, it is anybody's guess about the history of the Norton down-draught twin head.

"I would not say that the 650 head came from the Domiracer, since the Domiracer did not appear in public with that head until several months after the Manxman was running with it, it is anybody's guess about the history of the Norton down-draught twin head.beng "

From Mick Walkers book "Norton Dominator" on the new 650 engine-
"Derived directly from that of the works Domiracer, the new light-alloy cylinder head featured widely splayed exhaust ports and parallel inlet tracts..."

I am often wrong about things but do not make things up, just not bright enough to be sucessful at it. The rest of the info about the increases to Atlas compression and cam change is also in the book, you might pick it up, or choose to believe Mick Walker is incorrect , no matter.

Glen