why is the norton atlas clutch such a bear?"

The clutch rollers are only rolling when the clutch lever is pulled in. Make that brief.
I am trying to come up with a low cost alternative to the Newby clutch, something less than $800+ dollars. The CHAIN MAN says people runthe chain in their Manx and it holds up well for a season.
 
We run 2 old Nortons and the primaries do not leave a puddle underneath. My latest wheeze is to use red rubber (silcon?) grease on the seal ,and it has worked for months.
 
I have a Tony Hayward belt drive in my Atlas and Goldstar. I uses a Triumph clutch center with loose and unlubricated rollers. It has held up just fine for years.
 
...A Teflon lined clutch cable by Venhill can reduced clutch pull by about 25%. This has made my Atlas clutch manageable....

Slick
I received mine last week. Waiting for the rest of my clutch parts before I assemble. I’m hoping it makes the clutch pull more bearable.
 
Re; “For a simple test this should be good enough. I told him to think about a jig of some sort, some easy way to bevel the driving edge of the plate. If I am going to pay someone to do this I want new plates and top accuracy.”

A tool and cutter grinder could do this in a dividing head as that is what I am planning to
 
Ed, I spoke to my friend and he reports that he hasn't noticed any "alarming" noises coming from his clutch.
Hope this helps.
John in Texas
 
Ed, I spoke to my friend and he reports that he hasn't noticed any "alarming" noises coming from his clutch.
Hope this helps.
John in Texas

Thanks John,
Did he describe the sound as any different from a non-modified clutch?
 
Hi all, this is an interesting thread and yet another "What might have been" if the management had taken interest at the time. One thing which may be of interest to you, Ludwig recently mentioned on the Commando forum that he uses "Linear" lined outer cable (As opposed to Spiral wound) for his clutch cables as they apparently have a number of advantages. They don't compress under load so transmit more of the movement, they give a smoother action with more feel and they are much harder to kink. Linear cables are used in the bicycling world for brakes and gear changers. I think a brake cable would be strong enough for a clutch.

Cheers,

cliffa.
 
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Hi all, this is an interesting thread and yet another "What might have been" if the management had taken interest at the time. One thing which may be of interest to you, Ludwig recently mentioned on the Commando forum that he uses "Linear" lined outer cable (As opposed to Spiral wound) for his clutch cables as they apparently have a number of advantages. They don't compress under load so transmit more of the movement, they give a smoother action with more feel and they are much harder to kink. Linear cables are used in the bicycling world for brakes and gear changers. I think a brake cable would be strong enough for a clutch.

Cheers,

cliffa.
So, he made his own cable from cable sourced from a bicycle shop? Interesting.
John in Texas
 
So, he made his own cable from cable sourced from a bicycle shop? Interesting.
John in Texas

It should be noted that some linear reinforced cable housings for bicycles are not used for brakes. They are used for shifting, where the compression load is minor, and the lack of friction imperative for the small movements of the cable. Regular brake housing is has wound reinforcement, just like motorcycle brake and clutch cables. There is specially designed, linear reinforced "compressionless" brake housing that you must use.

The regular linear reinforced shift housing is only compatible with cables up to 1.2mm and will split with as much compression as a stiff clutch, leaving you in a worse position than you were before.

The compressionless brake housing takes up to a 1.5mm cable and will hold up to a clutch. This stuff is stiff and doesn't make bends easily, so make sure your routing is clean.
 
Modern m/c clutches use ramps at the clutch center acting on the spring disc (or diaphragma) to obtain the desired clutch slip and self servo effect .

https://www.kawasaki.co.uk/en/about...ch?Uidth=0560WlhZXFhZWlBZXVlbWVteUVlaRg0GRT0j

Self-servo or booster clutch:
https://www.schaeffler.com/remoteme...s/schaeffler_2/api/downloads_13/obk_de_en.pdf

-Knut

Regretfully, Schaeffler does not offer a self servo clutch for the Norton Atlas. If they did, it would likely cost a pile of Franklins as high as the clutch stack. The Heinz mod seems to be the best alternative.

Slick
 
It should be noted that some linear reinforced cable housings for bicycles are not used for brakes. They are used for shifting, where the compression load is minor, and the lack of friction imperative for the small movements of the cable. Regular brake housing is has wound reinforcement, just like motorcycle brake and clutch cables. There is specially designed, linear reinforced "compressionless" brake housing that you must use.

The regular linear reinforced shift housing is only compatible with cables up to 1.2mm and will split with as much compression as a stiff clutch, leaving you in a worse position than you were before.

The compressionless brake housing takes up to a 1.5mm cable and will hold up to a clutch. This stuff is stiff and doesn't make bends easily, so make sure your routing is clean.
This is the aforementioned thread..

https://www.accessnorton.com/NortonCommando/custom-cable-kits.26871/page-2

It's true that under load these cables can "blow" as it's apparently known, however the quality ones are Kevlar reinforced so can take a lot more load. I agree that routing them needs more planning, but for a clutch which only normally has two bends it should be possible. Anyway, I have ordered one from the U.K. (Odyssey Linear Slic Kable Brake Cable with K-Shield Housing) and hope to give it a go on my Commando in a few weeks.
 
This is the aforementioned thread..

https://www.accessnorton.com/NortonCommando/custom-cable-kits.26871/page-2

It's true that under load these cables can "blow" as it's apparently known, however the quality ones are Kevlar reinforced so can take a lot more load. I agree that routing them needs more planning, but for a clutch which only normally has two bends it should be possible. Anyway, I have ordered one from the U.K. (Odyssey Linear Slic Kable Brake Cable with K-Shield Housing) and hope to give it a go on my Commando in a few weeks.
Why don't you give us all you take on how that goes, I'm sure that I along with others would be interested. Is it a pre-made cable or will you have to make your own?
John in Texas
 
Regretfully, Schaeffler does not offer a self servo clutch for the Norton Atlas. If they did, it would likely cost a pile of Franklins as high as the clutch stack. The Heinz mod seems to be the best alternative.

Hi Slick,
#73 wasn't meant as a proposal. Sometimes it's interesting to look into what others do. This sideview highlights the shortcomings of the trial solution by Heinz. His mod is certainly not the best alternative from a technology point of view but certainly the most economical and quickest to realize. It would be nice if the symptoms of deformed plain plates and grooves in the slots disappeared when fitting modified new parts.

-Knut
 
Why don't you give us all you take on how that goes, I'm sure that I along with others would be interested. Is it a pre-made cable or will you have to make your own?
John in Texas
It's pre made, but for sure I'll need to adapt it. Ludwig is one of the guys I really respect on this forum, if not I would not even waste my time.

I will certainly send updates.
 
Hi Slick,
#73 wasn't meant as a proposal. Sometimes it's interesting to look into what others do. This sideview highlights the shortcomings of the trial solution by Heinz. His mod is certainly not the best alternative from a technology point of view but certainly the most economical and quickest to realize. It would be nice if the symptoms of deformed plain plates and grooves in the slots disappeared when fitting modified new parts.

-Knut

Yes, Knut, I read that as something interesting and informative of what modern technology is up to, and not a proposal. I wanted to keep the discussion on track as to what we could realistically do about the Atlas clutch pull. Your statement " (Heinz) mod is certainly not the best alternative from a technology point of view but certainly the most economical and quickest to realize" puts it in very good perspective.

Regarding: "It would be nice if the symptoms of deformed plain plates and grooves in the slots disappeared when fitting modified new parts." This is called 'cratering' of the clutch center, and seems to be something we have to live with the AMC clutch as it has evolved to its overloaded state in the Atlas, 650SS, and the hybrid variants. One extra friction and plain plate pair were added in that evolution to gain more torque capacity. The down side of that modification was that all plates were thinner, and this decrease in thickness increased the bearing stress on the clutch center and the plate tabs. And so, not much we can do about that, except to refrain from clutch abuse (no more wheelies, speed shifts and racing away from every stoplight), although harder materials are used in newly made parts, and the problem seems to be less that it was.

I asked a question in reply number 18 .... is there any backlash when engine braking? That question was meant to explore whether the cratering problem is worse with the Heinz mod. I can visualize the plates slamming back and forth in that 19 degree gap in the clutch basket when suddenly engine braking. Not saying that such slamming will happen, but just a concern. So far no answer from John on that point.

BTW .... the Kawasaki link you provided states "When excessive engine braking occurs – as a result of quick downshifts (or an accidental downshift) – the slipper cam comes into play, forcing the clutch hub and operating plate apart." This describes the backlash effect that I am concerned about.

Slick
 
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