Clutch nut falls off!

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Staytite

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I went out for a little pootle about on my Commando yesterday in the sun and had the embarrassment of having to be recovered on a truck.....

The clutch nut had almost completely undone itself. As per another threads it seems the tab washer is too soft and had been battered thin
allowing the nut to come lose. On closer inspection it would seem the clutch nut is a reduced hax nut with very little contact with the clutch centre.
See photos in the cracked clutch thread below. The available face on he nut is very narrow ring little more than 1/8 wide and the clutch has a hole
larger than the face are of the nut. Why is a reduced hex nut used? it looks like a full size one could fit?

Has anybody changed to a full size hex 5/8" x 20 TPI nut?
 
Staytite said:
I went out for a little pootle about on my Commando yesterday in the sun and had the embarrassment of having to be recovered on a truck.....

The clutch nut had almost completely undone itself. As per another threads it seems the tab washer is too soft and had been battered thin
allowing the nut to come lose. On closer inspection it would seem the clutch nut is a reduced hax nut with very little contact with the clutch centre.
See photos in the cracked clutch thread below. The available face on he nut is very narrow ring little more than 1/8 wide and the clutch has a hole
larger than the face are of the nut. Why is a reduced hex nut used? it looks like a full size one could fit?

Has anybody changed to a full size hex 5/8" x 20 TPI nut?
Click to expand...

No, but I keep a stock of Belleville washers. That and a little blue locktie cures the problem. Jim
 
Hi Jim

Thanks for the reply, while you were replying I sent you a PM - possible the two messages passed each other over the Atlantic!

But why the reduced hex nut?

Seems strange - did Norton have a surplus bucket load of reduced hed nuts that need using up?

Thanks
Martin
 
Staytite said:
The clutch nut had almost completely undone itself. As per another threads it seems the tab washer is too soft and had been battered thin allowing the nut to come lose. On closer inspection it would seem the clutch nut is a reduced hax nut with very little contact with the clutch centre.
Click to expand...

You don't mention the flat steel washer [58] 06-3447 which should also be fitted.

https://andover-norton.co.uk/en/shop-dr ... lternator#
https://andover-norton.co.uk/en/shop-de ... tch-fixing

If the later tab washer is used then it should have the flat washer between the nut and the tab washer (but not the earlier lock washer used before the tab washer was introduced).
 
Hi L A B

Sorry I forgot to mention that I had fitted the correct hardened steel washer in the correct place.
(This getting old business is not good for me - or the Commando!)

That washer seems a bit small as well!?

Thanks
Martin
 
Staytite said:
That washer seems a bit small as well!?
Click to expand...

I think the 06-3447 flat washer is 7/8" O.D. As it goes between the nut and the tab washer if it was any larger diameter it would obstruct the tabs when they were folded against the nut.
 
Hi kerinorton

I had read the split nut string and as you can see (and not see via PM ) I am in contact with Comnoz.

I think the belleville with locktite is the way to go. Just need to sort the ID (16mm) to go over
the gearbox main shaft and the OD (28mm?) of the raised boss on the clutch centre and thickness
which presumably gives the pressure force?

16mm ID belleville washed tend to have an OD of 31.5mm and is that ok?

Sorry to work in the French metric system on a Norton - wash my mouth out with Castrol R

Thanks to all
 
Manual is wrong. 40 ft. lbs. torque not 70. Also mainshaft clutch basket support circlip is easily crushed creating sloppage. Use stronger MK 111 circlip 06-8072 , sand down a tad ( thickness) , to fit tightly onto shaft. Bellville washer and blue locktite yes .
 
Torontonian said:
Manual is wrong. 40 ft. lbs. torque not 70. Also mainshaft clutch basket support circlip is easily crushed creating sloppage. Use stronger MK 111 circlip 06-8072 , sand down a tad ( thickness) , to fit tightly onto shaft. Bellville washer and blue locktite yes .
Click to expand...


Use stronger MK 111 circlip 06-8072 , sand down a tad ( thickness)

This works great. The only problem is -last time I tried to get a batch of them they weren't available. I will have to try again. jim
 
Torontonian and Comnoz,
These circlips are listed as in stock at both RGM and Andover. However, they are listed as a starter motor circlip. Is 06-8072 the correct part #?

Ed
 
APRRSV said:
Torontonian and Comnoz,
These circlips are listed as in stock at both RGM and Andover. However, they are listed as a starter motor circlip. Is 06-8072 the correct part #?

Ed
Click to expand...

Yes, that is what it was used for. Jim
 
Hi

Hi All

Comnoz is a superstar and the belleville washers are winging their way over the Altantic ocean.

I have fitted the starter motor circlip.

I have a nice new bottle of loctite

Now, what about using a full size nut rather than small hex to give a greater surface area to the "locking" face?

More surface area will give more friction resistance and a more even pressure, will it not?

And a full size nut in 303 stainless ? Is 303 tough enough to talk the talk (Torque)?

Thanks
 
Staytite said:
Hi

Hi All

Comnoz is a superstar and the belleville washers are winging their way over the Altantic ocean.

I have fitted the starter motor circlip.

I have a nice new bottle of loctite

Now, what about using a full size nut rather than small hex to give a greater surface area to the "locking" face?

More surface area will give more friction resistance and a more even pressure, will it not?

And a full size nut in 303 stainless ? Is 303 tough enough to talk the talk (Torque)?

Thanks
Click to expand...

I think I would stay with the stock nut. I know it works with the Belleville washer. Not so sure about the larger nut. Just keep the torque down to 40 or 45 lbs. Jim
 
Blue Loctite is good stuff. Once when I was working in a defence area, someone used it on every exposed nut on a fighter plane.
 
Or you could do this , no need to have to lock the clutch up to do up/undo
Regards Mike
Clutch nut falls off!
 
Hi Mike

It was the 5/8 x 20 TPI small hex nut that holds the clutch centre onto the
gearbox mainsheet, not the ajuuster lock nut.

Regards
 
Agreed, as I have an exposed clutch on my race bike.
I have done the same for the roadbike behind the primary cover, if I need to adjust the clutch at any stage , I do so on the handlebar adjuster.
The clutch comes apart once a year for maintenance, and is a belt drive , so not really an issue for me .
Just another perspective.
I have done the same for the race bike center hub nut.
Regards Mike
 
Hi Mike

The problem seems to be the soft tab washer behind the clutch centre nut.

Do you omit that in preference for the lock wire?

Thanks
 
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