Clutch Drum Sorting

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Al-otment said:
hobot said:
All the clutch nut clamping only bares down on the wimpy locator circlip you found by accident. There's a slighty heavier duty circlip version but I don't have a part number. Clutch shims, if needed go on face of the relieved spacer to line up drive pulleys. If clutch too tight, going by listed torque it can overwhelm circlip, if too loose comes off away from home. Generally just shim so basket don't rub inner case gets it close enough for chain life but two carpenter squares butted on the pulley faces can guide the best.

I've only found a problem with the circlip if it's re-used. New one on assembly, loctite and 70lbft torque. Before I had a suitable torque wrench the nut would come loose at sustained high speed. Increasing the torque from 50lbft to 70lbft cured this. To align sprockets, as per Mick Hemmings. Straight edge across clutch drum circumference and measure distance to teeth. With straight edge projecting across engine sprocket measure to teeth - difference is adjusted with shims behind clutch hub.

Hobot mentioned heavy-duty circlip used for the clutch groove, which would be the 06-8072, Item #15 for the backfire device shaft. It is for Mk III starter but is used sometime for this application. Its about 0.017” thicker (0.045” as to 0.062”) and you may need to strop it by using a flat plate and sandpaper to make it fit in the groove. I would use Loctite 243 with that nut and the Belleville washer is a good idea, as the tab washer tends to be too soft. The star washer on the rotor is also a “one use only” application and many a rotor came loose because of this washer getting flattened and worn smooth. Buy spares and Loctite is your friend here.
Cheers,
Thomas
CNN
 
CanukNortonNut said:
Hobot mentioned heavy-duty circlip used for the clutch groove, which would be the 06-8072, Item #15 for the backfire device shaft. It is for Mk III starter but is used sometime for this application. Its about 0.017” thicker (0.045” as to 0.062”) and you may need to strop it by using a flat plate and sandpaper to make it fit in the groove. I would use Loctite 243 with that nut and the Belleville washer is a good idea, as the tab washer tends to be too soft. The star washer on the rotor is also a “one use only” application and many a rotor came loose because of this washer getting flattened and worn smooth. Buy spares and Loctite is your friend here.
Cheers,
Thomas
CNN
I am going to add to this just a little.
There is usually a burr side to the circlips. In all applications in general, the burr side goes toward the direction of the force/work being applied. We are tightening toward the gearbox so the burr goes towards the gearbox.
 
Yes many parts stamped out so one edge more square-sharper, so worth while to check clutch plates to face sharper dragging edge outward so lever hand over comes that and less for spring force resistance to clamp back together. Might be worth while to see how much torque to over come the standard circlip you are trashing anyway to get a feel or measure for what to use on the new one. I have by accident in past.
 
bwolfie said:
I have the replacement clips and beleville washers available.
The clip is a bit fiddly to get installed, but offers a positive engagement of the entire shaft.
I also have belevile washers for the alternator.

$5 each shipped.


PM SENT...........
 
olChris said:
Bugger .. i was just searching their site but couldnt find centre and mainshaft.. so sent email to AN for quote... but contact R&R

Some of the Andover parts pages are a little hard to see clearly,I found this some time back on another site.
Very clear and easy to navigate,a good range of Brit bikes covered also.
http://www.bigdcycle.com/books.html

Good one Big D and all the other venders out there that make it possible to order Norton parts like it was 1974 again. :D
 
Have you been inside the gearbox/transmission yet.
I had removed the one from the 850 and got round to looking inside today.
The bush in the 'kick start gear was breaking up but the box in general looks pretty good.
I am fairly sure both my 750 and 850 have not been touched trans wise,the 750 had a ball layshaft bearing with 'Gt Britain on it.
What did I find in the 850.

Clutch Drum Sorting
 
But how important is that circlip??

I have just fit new bearings, bushings, gaskets, seals, the whole nine yards.

Inner cover is snug, and I went from the original 19T to a 21, old man that I am. everything went together well, until now.

Now I have the spacer on the clutch side of the mainshaft, but the shims won't fit beneath the clip;

Clutch Drum Sorting


If I omit the clip, add the shims, the clutch drum fits nicely;

Clutch Drum Sorting


there is very slight endplay in the mainshaft, about .005"

Does anyone have similar experience? I want to get all this fitting correct before replacing the primary

Buku Thanks!

Don
 
First the inner primary cover, then the circlip, then the clutch locating washer (060747), then the shims as needed to align the hub to the crank sprocket.
 
...it may be the hour of the day or my failing eyes but is the sprocket retaining nut in your pic on backwards?
The recess in the washer is intended to keep the clip from spreading, so inner case, clip, washer recess against clip, appropriate shims as previously noted.
All the Best.
 
Many thanks for you responses, gentlemen. Now it makes sense;

Clutch Drum Sorting



AntrimMan, I don't know if that sprocket nut has a front or back, the Haynes book I have simply says to torque it to 80lbs! Not having a deep socket that big, I just gave it my best with a box wrench and some locktite.
 
The nut is, in fact, backwards. You are loosing much contact between the nut and gear. Not good in such a critical area. Good thing that it is still accessible. Sorry. Better fix it.
That o ring or the extra felt is a good idea though. I like that. Anyone with questionable bushes would really benefit from that.

One more thing. Make sure the sharp/burr side of the circlip faces the gearbox.
 
thanks Pete, no biggie to take it off and flip it over.... what do you mean by "questionable bushes"? does the felt wear out? (when I took it all apart, there was no felt at all, 40 years later, hehe)
 
DonOR said:
thanks Pete, no biggie to take it off and flip it over.... what do you mean by "questionable bushes"? does the felt wear out? (when I took it all apart, there was no felt at all, 40 years later, hehe)
No, what I think Ludwig was referring to the o ring, gear oil can pass through the sleeve gear out onto the main shaft and consequently contaminate the clutch. If the sleeve bushes are on the worn side or even if they are not, the o ring in this location (or felt) will help in this regard.
 
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