Atlas 650, 600,500 cast iron barrels –the truth!

Bernhard

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Recently on this website someone stated on another thread the c.i. barrels on an Atlas have on spun cast liners inside them-you know how it is –it only takes someone on social media or the internet to make a statement which then becomes a “Fact”
I quote,

Postby texasSlick » Thu Apr 13, 2017 2:01 pm
I happen to have my Atlas cylinders sitting on my credenza. As I am the original owner, I can attest to the fact these are as originally fitted.
Examination with a 5X loupe reveals:
1) There is a uniform sand casting texture where the outer diameters of the cylinders join the base between the tappet bores (the non machined area inside the gasket flange). There is a smaller non machined area at the rear, dead center between the cylinders, that has the same texture characteristics.
2) There is also a generous radius where the outer diameter of the cylinder joins the non machined base area.
3) There is no visible joint in the machined surface where the lower cylinder spigots merge into the tappet bores.
These factors rule out a pressed in liner. Let's put this issue aside and return to helping the OP with his original question. Slick
 
What are you saying Bernhard? They do or do not have liners from the factory?

Ed
 
APRRSV said:
What are you saying Bernhard? They do or do not have liners from the factory?

Ed
Click to expand...

1. I think Bernard is saying forums are a great source for misinformation and whether many posters are functionally illiterate and not clear in their writings or just give bad data because they heard it else where (parroting).
I agree. See my by-line below

2. He quotes Slick: where Slick goes through great pains to prove his point, which is correct. They (atlas24237) did not come with CI liners. To expand on that...if you look...750 commando used the same # raw casting. 24237

While commando maybe king on Access Norton...There is such a distinction to separate early NHT from the last 7 years (commando) from the NHT roots 1949-1967. Which is a sample of where this forum is (IMO) a poor format. You can't speak of early bikes on the commando section and you are not supposed to speak of commando on the norton "other" section.
Why is P-11 so special ??????????????????

For mainly these reasons, I have little to say.
 
Bernhard said:
Recently on this website someone stated on another thread the c.i. barrels on an Atlas have on spun cast liners inside them
Click to expand...

There is somewhat of a MAJOR FLAW/TYPO in Bernhards statement here, which doesn't help !!
Is he trying to say there is NO sleeve ?? - not "on" (sic )

As before, I'd comment that I have more than a few examples of Nortons iron cylinders,
and NONE of them have sleeves from the factory. Dommie 500, Atlas 750, Commando 850
Including a set of usable but worn Atlas cylinders, still at std size, but needing a rebore to +0.020
No sleeves in that one either, Bernhard.

The spun cast sleeves were offered ONLY as a repair item.
Since the WW2 era even, for the military models.
Bernhard is offering silly comments about them being sleeved from new from the factory.
Since Dave couldn't quite get around to saying this clearly.
Lets not beat around the bush....
 
Aren't you all in violent agreement that Norton Dommie cylinders were cast iron thru and thru?

Glen
 
Bernhard doesn't seem to be.... ?
And Dave also seemed to beat around the bush a bit ?

And if the words, and thread title, are misleading/unclear as to meaning,
I thought I'd stamp on any suggestion that Norton cylinders aren't one piece iron castings through and through,
for the benefit of future readers.

I had wondered if this is an example of "alternative facts", as seem to be becoming popular !!
 
beat around the bush?

"Slick goes through great pains to prove his point, which is correct. They (atlas24237) did not come with CI liners.
 
Many folk would be wondering at this point what a CI liner was ?
And, how that relates to the spun cast liners that ARE available

Or, by you stating did not come with CI liners.,
do you really mean they came with steel sleeves ??
Nortons used steel sleeves in their racing engines - Manxs and Inters - for ooh, about 30 years.

Beating about the bush here, definitely.....
 
Yes we're taking about norton twins....initially atlas but it really includes 750 commando.
NOT
"Nortons used steel sleeves in their racing engines - Manxs and Inters - for ooh, about 30 years."

back to my normal mode: :mrgreen:
This post was made by Rohan who is currently on your ignore list. Display this post.
 
Surely even you can see that saying that
Nortons didn't have cast iron sleeves
is NOT the same as saying that Norton twin engines didn't use sleeves.

That ambiguity is beating about the bush for sure.....

We still haven't heard from Bernhard about his take on this either...

And, in case anyone has lost the historical perspective on this,
the dommie and Atlas and 650 engines were designed at Bracebridge street,
in the era when Nortons WERE fitting steel sleeves to some of their engines...

Or as Dave might put it
in the era when Nortons WERE fitting steel sleeves to some of their engines.
 
Bernhard has been unable to respond as the accessnorton server has been rejecting his message when he attempts to post it (although I think the technical problem has been identified :lol:) so he asked if I would post the following message on his behalf.


Bernhard said:
To all those who dispute my version here’s my reply;
I have read your comments, now read mine;
My Atlas was only 5 years old when I purchased it, are you suggesting it had done a high mileage –there was no indication on the cycle parts because I would have spotted it.
I have just examined a 500 Domi barrel-an even earlier one to the Atlas -as it has the dynamo str*p on the front. Looking at it on the absolute bottom there appears to be no indication of a liner, however, when I rubbed some of the dirt and grime off the bottom of the cylinder with some coarse emery cloth it has, without question, an inner liner in there. So, I will ask you politely to clean up the bottom of the cylinder like I did and look again, if you have 20/20 eyesight – you will not need a loupe to see that there is, as I said all along, a spun cast liner in the cast iron barrels. When you have done that could you please post pictures of your handiwork to this website so no one ever again makes the same mistake

N.B, if the barrel was 100% cast iron there would be a lot more barrels with part of the top spigot broken off as cast iron is brittle :!: :shock:
Also, c.i. can become porous
Liners were made from spun cast iron- a stronger material and not as brittle as than c.i.
RGM liners;
http://www.rgmnorton.co.uk/csi/1245184/ ... rawing.pdf

close grained spun cast cylinder liners. - RGM Norton
http://www.rgmnorton.co.uk
L D A H Chamfer Lead in at finished bore diameter 600 SINGLE P/N = 050049 A= 81.5MM B = 85MM+/-.01MM L = 190MM D = 94MM H = 10MM 920 TWIN P/N = 050016 A = 80MM
Click to expand...
 
I now own 24 NHT engines 1950-1975 dynamo and alternator 500, 600, 650 750 and 828 and several more spare barrels. None show any evidence of being sleeved. (Except an aluminum 920 barrel) I have several BSA A-10 barrels that are unmistakeably sleeved.
However one very low mileage bike, in less than 5 years, can certainly be trashed and in need of sleeving service. I totally trashed my first brand new 70 commando in less than a year. In less than 3 years I sold it as a assembled basket case with 3000 miles. It needed a whole lot more than a sleeve :lol:
 
Indeed.

No sleeves in this one Bernhard !

Selected at random, Ive got a few of these spare, NONE of them have been sleeved.
This one is a good candidate to be sleeved though, those spigots are getting rather thin,
no room for another rebore....

Atlas 650, 600,500 cast iron barrels –the truth!


As far as I've seen, ALL Nortons with iron cylinders are just a solid iron cylinder, no sleeve necessary or fitted.
It was only done as a repair option....
 
Well……it looks like I am going to have to eat my words :!: :(
It is strange that I have never seen a Norton heavyweight twin c.i. barrel without spun cast liners they surely are not as common as you are leading to believe, if anyone had a 100% c.i. barrel then when it is taken to max rebore, you will have to pay for the barrel to be bored to take a spun cast liner also under cut at the top to take a flange of the liner which stops it dropping down inside the barrel-don't ask me how I know :!: :shock:
 
Bernhard said:
Well……it looks like I am going to have to eat my words :!: :(
It is strange that I have never seen a Norton heavyweight twin c.i. barrel without spun cast liners they surely are not as common as you are leading to believe, if anyone had a 100% c.i. barrel then when it is taken to max rebore, you will have to pay for the barrel to be bored to take a spun cast liner also under cut at the top to take a flange of the liner which stops it dropping down inside the barrel-don't ask me how I know :!: :shock:
Click to expand...

I certainly can't take away from your experience.
I can make one comparison that may or may not be true. Here in the USA the bikes died very early for lack of competent servicing capability.
Even to this day here in New England approximately the size of UK, we only have one norton club with under 100 people. In all of New England there is not one Norton repair shop that I recommend for Norton servicing. Our club constantly help members recover from the butchery that the generic Brit repair shops inflict on their machines.
I currently have one bike that had $16,000 billed for a restore. I have it in here for a fair amount of corrective actions.
The residual Norton fleet are probably extremely different than what you have in the UK. Many bikes are barn finds with under 10000 mile still on original bore. A fair amount my barrels are std bore. Some are +20 and a couple +40. I recently acquired std 500 alternator barrels (marked 88SS) for my 1959 88 engine, and my M7 dynamo barrels are still std. The small cylinder engines seem to suffer more since I have several but they need sleeving. Almost all commando and atlas barrels can accept a regular oversize bore if needed.
Competent service is very tough to find. I obviously would rather do my own work.

I have an old saying:
Why pay some one else to screw it up, when I can screw it up for FREE. :mrgreen:
 
Also, what would be the point, as sleeving new barrels would only seem to add unnecessary machining operations and expense?
If some barrels were sleeved from new, and that is if, then the only logical reason to do so I can think of, would be to save a barrel casting where the boring hadn't been done correctly or had exposed a flaw in the casting, but would they have gone to the trouble of sleeving a reject instead of throwing it in the scrap bin?
 
L.A.B. said:
Also, what would be the point, as sleeving new barrels would only seem to add unnecessary machining operations and expense?
Click to expand...

Indeed.
And why would they sleeve BOTH cylinders in a reject ??
The whole idea of cast iron cylinders was cheap cheap cheap to produce.
Cast it, machine it, plonk it on an engine.

If one sleeve moved in service Bernhard, then the sleeving wasn't even done correctly.
Since the sleeve gets hotter in action than the surrounding cylinder, it is VERY firmly locked in place,
since sleeves can only expand outwards with heat. As long as the interference fit is done correctly...
 
Rohan said:
Indeed.
And why would they sleeve BOTH cylinders in a reject ??
If one sleeve moved in service Bernhard, then the sleeving wasn't even done correctly.
Since the sleeve gets hotter in action than the surrounding cylinder, it is VERY firmly locked in place,
since sleeves can only expand outwards with heat. As long as the interference fit is done correctly...
Click to expand...

I explained in a previous thread why one liner dropped down in the barrel -nothing to do with anything Norton or otherwise did.
 
If I was to race this new found 650 SS I have in the 500 class, what would be the best way to go about it?
I will leave as is to race in the open class until my 850 is back together.
Restroke in a set of 500 barrels or what?
Regards Mike
 
Brooking 850 said:
If I was to race this new found 650 SS I have in the 500 class, what would be the best way to go about it?
I will leave as is to race in the open class until my 850 is back together.
Restroke in a set of 500 barrels or what?
Regards Mike
Click to expand...

Don’t quite see why this is on here, but a 650 will hardly qualify for the 500 class if 500cc is the upper class limit :!:
 
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