Commando gear teeth thread.

[Rohan]

H**y C**p.
I thought we were going to have a thread on gearboxes.
You obviously have other ideas.

 

[JimNH]

Since I'd like to continue my education I suggest the thread continue.

B. Rad could develop a little thicker skin.

Rohan could try being polite and respond with facts rather than assertions.

We could all stay on topic and keep opinions that suggest our bike are suitable for some maritime use out of the discussion.

Jim

 

[Rohan]

Or more accurately the hertzian contact stress causes sub-surface fatigue

OK, lets put it this way.
This phrase hadn't been invented when Norton gearboxes were first designed, tested and successfully used.

What does that tell us ?

 

[Rohan]

Since I'd like to continue my education I suggest the thread continue.

Good comments.

Where are we going to get these 'facts' though on Norton gearboxes, when the technical book on them hasn't been written yet,
and no-one has yet shown anything detailed on them.
My FACT that Norton gearbox tooth counts always sum to 42 is the only solid Norton fact yet presented ?,
if we are not going to accept assertions.

The NOC has a chart of all the tooth counts and shafts used, but appear to have made it off limits to outsiders.
There is also, somewhere, a chart of tooth angles and fillet radii.

Without facts to discuss, all we can do is .....

 

[B.Rad]

Or more accurately the hertzian contact stress causes sub-surface fatigue

OK, lets put it this way.
This phrase hadn't been invented when Norton gearboxes were first designed, tested and successfully used.

What does that tell us ?

That you are wrong

Well Rohan, toe to toe it is then. Thats fine. but there is a general rule that says when you are in a hole stop digging.


So to test and rebutt your latest claim that hertz stress were not invented when Norton boxes were first designed.

Reference : Hertz, Heinrich: On The Contact of Solid Elastic Bodies and on Hardness, J. Math,. Vol 92, 1881, pp 156-171

I dont know what will convince you that this is fact. it may be impossible

I find it incredible that a person with no gear industry experience can speak as if he is an authority on gear design and believe he is the only one that state facts. its like trying to argue with the Taliban.

Rohan, keep on trying. I am going to continue because some persons have expressed a genuine interest in this subject. i await your further attempts at hi jacking.

 

[Hobot]

People who tend to ride hard are hot heads from the get go and reason only about 10% tolerate online forums. The last few years of Norton Commando racing wonders were almost all prevented from wining or placing very well against more moderns d/t transmission failures nothing else. The now late Norton drag races I pow wowed with said once ya got the think making some decent power close to or over 100 hp the AMC spilled their gut on the track so moved to Harley solution again. California market required noise reduction and reason for 860's 2nd gear, T tube exhaust and black cap baffles.

The lightness of rider and bike plus size of tire patch matter to teeth loads and can attest it takes upper 70's lower 80's to send a P!! with tall 1st and close ratios into mid upper 10's second 1/4 m E.T.'s time and time and time again and again till clutch stuck up but trany fine to break free by snicking from N roll off into 2nd while nailing it. Too bad not many of us ride like that any more for a makret Bradly could well serve.

 

[Stephen Hill]

I would be happy if we could determine if and when the gears were made stronger (versus just changed in the number of teeth), and also get a bit more advice on which gears are truly interchangeable, as in you don't need to swap out pairs.
It would also be cool if we could build a table by year showing detailed changes around the gears, shafts, and shells from 1960 to 1975.
But perhaps I am just hallucinating.......

Stephen Hill

 

[Kvinnhering]

Since I'd like to continue my education I suggest the thread continue.

B. Rad could develop a little thicker skin.

Rohan could try being polite and respond with facts rather than assertions.

We could all stay on topic and keep opinions that suggest our bike are suitable for some maritime use out of the discussion.

Jim

+1

 

[Rohan]

I would be happy if we could determine if and when the gears were made stronger (versus just changed in the number of teeth), and also get a bit more advice on which gears are truly interchangealbe, as in you don't need to swap out pairs.
It would also be cool if we could build a table by year showing detailed changes around the gears, shafts, and shells from 1960 to 1975.
But perhaps I am just hallucinating.......

The NOC had the makings of this on their website until (quite) recently,
bit it has either gone or no longer viewable from outside.
It was more detailed for the wartime models than for more recent though.

 

[Rohan]

Anyone know where AMC boxes fit into this scheme ?

 

[Rohan]

Reference : Hertz, Heinrich: On The Contact of Solid Elastic Bodies and on Hardness, J. Math,. Vol 92, 1881, pp 156-171
.

Woo hoo, you quoted a reference , you do know something !!!
May there be many more.....

 

[Rohan]

That actually leads on to the next question.
The AMC Norton boxes were made for them by Burmans.
(They may have read that reference, but would anyone in Nortons ?)

Anyone know what happened to Burmans, or more precisely their documentaion of the gearbox business.

They'd been making gearboxes back to the early part of the 20th century,
And would have had all the documention on the AMC boxes.....
Not to mention the laydown, upright and doll head boxes before them.

 

[texasSlick]

@B.Rad

Thank you for an educational post. The Forum could do well with more such, for these are informative to lay persons struggling to keep our beloved classic Brits operational, put comprehensive info in one place, and should be interesting to the more knowledgeable.

It is a shame such posts become polluted with extraneous injections, wisecracks, and comments.

Perhaps Jerry, who has asked for new Forum ideas, would create a technical category where such posts could be placed. Then, as is done with publications in professional journals, critics would have ONE chance to comment, the author invited to respond, and no further comments by the critic allowed for that particular post. In that way, someone trying to glean information would not have to wade thru reams of non applicable posts to get to something worthwhile, or follow a torturous side-path before getting back to subject. For me, such diversions make me bored, and I abandon the thread, perhaps losing some info of great value to come after.

Ultimately, the Forum should be "brothers helping brothers" to keep our Nortie girls proud and strong. An educational post is of high value in this regard.

Slick

 

[Rohan]

As I said earlier, if posts could be developed into a full article, with attached pics to illustrate the text,
and even references to support the content.
As Stephen suggested too, a chart or table of the gears, shafts etc that go into Norton boxes over the years.

I'd also comment that in a past life I used to proof read articles and techical articles before printing/publishing,
and some articles had to go back for correcting/editing, sometimes more than once.
Sometimes they needed more, like a complete rewrite !

 

[Cheesy]

Or more accurately the hertzian contact stress causes sub-surface fatigue

OK, lets put it this way.
This phrase hadn't been invented when Norton gearboxes were first designed, tested and successfully used.

What does that tell us ?

Do you have a reference for this statement or is it made up to be argumentative???
DP for the AMC box is in the first post of this thread

 

[Rohan]

Do you have a reference for this statement or is it made up to be argumentative???

Getting info is sometimes like extracting teeth, if the subject doesn't want to assist....
Missed the DP in the noise though, thanks bothly.

Since we haven't had a single pic of the gears under discussion, here is a whole bundle of them.
Selected at random off fleabay, great photography.

 

[B.Rad]

I would be happy if we could determine if and when the gears were made stronger (versus just changed in the number of teeth), and also get a bit more advice on which gears are truly interchangealbe, as in you don't need to swap out pairs.
It would also be cool if we could build a table by year showing detailed changes around the gears, shafts, and shells from 1960 to 1975.
But perhaps I am just hallucinating.......

Stephen Hill

gidday Steve
yes mate, I am progressing to that very goal. gearing is a very very big subject.
Full libraries have been written about this subject. Many dissertations have also been written.

So for those following this , all I can say is I will continue to the best of my ability.. The purpose of this thread is to discover the changes to the AMC box and for interest only try and provide information for educational purposes.,

the subject may cover by necessity pre-Commando but will try and stay true to the title. it will not cover Burman.

I cannot because of time and space limitations write a article that can be as long as "Days of Our Lives".

this is not a dissertation for a PHD. So I will not provide referencing in an academic manner. but if necessary I will
LAB has provided much necessary and very helpful information and hopefully will continue to do so.
being a large subject I do ask for patience .

I do have trouble posting and I will try and get around that problem.
So, here we go.
before the next post, I will summarise what has gone before.
1. some definitions.
2. Pitch circles and the function
3. Standard tooth sizing, eg DP. The Commando uses the 10DP size tooth
4. circular pitch
next post will start to look more closely at a tooth
Aussie Bradley

 

[Cheesy]

Do you have a reference for this statement or is it made up to be argumentative???

Getting info is sometimes like extracting teeth, if the subject doesn't want to assist....
Missed the DP in the noise though, thanks bothly.

You still havent explained why you think hertzian contact stress was not known about when the AMC box was designed?? It is a very common design consideration in rolling, sliding and even static loadings.

Here is a more useful picture Edit to add 1971 750 gear set

 

[Norton Dave]

 

[B.Rad]

Thanks Dave. good of you to do this.
I have a good story to post but really struggle to deal with this photobucket stuff.
to All. Please bear with me . I will get my stuff here soon.
thank you