B31 Help - Clutch re-assembly - clutch not working

[neil1964]

You would be very hard pushed to overtighten that nut, chief thing is that there are no previous owners bodges as to why anyone would put the soft tab-washer behind the centre basket?

cdsdoorset2 was referring to the large dished washer that goes on before the chainwheel and centre bearing (this has contact with those corks on the backside of the chain wheel).

Just checking the centre but  is the one with built in washer flange  and a cutout for you to bend the tab washer over into?
Tighten with a moderately long lever should be fine, but your threads should be really clean and at final assembly (ie when you have confirmed that it all spins properly) I would use a couple of drops of Loctite Blue 243 thread locker (everyone with an old bike needs a tube of that to help avoid things dropping off!)

A point to make is that the two centre bearing cages can be assembled incorrectly on the inner race and it is also possible to have the inner race binding too (see text and pics re4ferred to below).

There is a useful thread here for a read and consideration:
https://www.britbike.com/forums/ubbthreads.php/topics/674773/bsa-6-spring-clutch
The author/poster can rather overdo the measurement/special tools bit but the pictures and information are very useful indeed.

I had to use an NEB clutch on my ABSAF 600 (too much power and torque for a stock clutch) but the same stock clutch with Surflex plates properly adjusted on my 57 Competition works beautifully.

[Fraz]

You would be very hard pushed to overtighten that nut, chief thing is that there are no previous owners bodges as to why anyone would put the soft tab-washer behind the centre basket?

cdsdoorset2 was referring to the large dished washer that goes on before the chainwheel and centre bearing (this has contact with those corks on the backside of the chain wheel).

Just checking the centre but  is the one with built in washer flange  and a cutout for you to bend the tab washer over into?
Tighten with a moderately long lever should be fine, but your threads should be really clean and at final assembly (ie when you have confirmed that it all spins properly) I would use a couple of drops of Loctite Blue 243 thread locker (everyone with an old bike needs a tube of that to help avoid things dropping off!)

A point to make is that the two centre bearing cages can be assembled incorrectly on the inner race and it is also possible to have the inner race binding too (see text and pics re4ferred to below).

There is a useful thread here for a read and consideration:
https://www.britbike.com/forums/ubbthreads.php/topics/674773/bsa-6-spring-clutch
The author/poster can rather overdo the measurement/special tools bit but the pictures and information are very useful indeed.

I had to use an NEB clutch on my ABSAF 600 (too much power and torque for a stock clutch) but the same stock clutch with Surflex plates properly adjusted on my 57 Competition works beautifully.

Thanks for the advice.
The whole bike has "previous owner issues" probably because it was used as a "show bike" and never ridden 

I've ordered a new soft tab washer and I'll assemble it as I did previously but I'll tighten it using hand tools and not the impact gun and see if the inner basket notes independently of the outer basket.

I'm also wondering about inserting the clutch plates . . . . .
Which goes in first?
Metal plate or friction plate?
(And which way do the raised "tabs" on the metal plates go? - facing the engine or outwards)
Sorry for the daft, newbie questions.

The link you provided was both interesting and mind blowing

[ducati2242]

You mentioned a domed washer next after the clutch drum . I cant remember that domed washer being fitted under the center . try it without it . If that indeed is how you fitted it .

[DAVE BRADY]

Hi,

Number 23 it the washer and rather than 'domed' it has raised edge.  It is a lock washer hence the tabs.  The domed should have a flat on it so that once torqued up, the edge of the washer is turned up to add the the security of the nut.

Dave.

[neil1964]

Hi,

Number 23 it the washer and rather than 'domed' it has raised edge.  It is a lock washer hence the tabs.  The domed should have a flat on it so that once torqued up, the edge of the washer is turned up to add the the security of the nut.

Dave.

Yes, I am referring to the nut (part 24 in the above diagram) that has a machined dome with a lip, so not a separate washer per se.  The lip pushes the locking washer against the pressed steel basket and the space inside the lip allows space for the bearing and hub centre internally, hopefully avoiding the issue that you inherited.

[scifi]

Is it possible that you are tightening the Clutch Spring Nuts down too much..?   They should not make the springs 'coilbound', and should each be individually adjusted to make the outer clutch plate lift off squarely.

[Fraz]

You mentioned a domed washer next after the clutch drum . I cant remember that domed washer being fitted under the center . try it without it . If that indeed is how you fitted it .

Thanks

[Fraz]

Hi,

Use a high melting point grease.  Just push it in until all spaces are full and wipe off any surplus leaving just a smear across the bearing.

Unless you are using a very long lever you would be hard pushed to over tighten the nut.  It locks all the centre bits together and they cannot be crushed.  If you are using a socket with a standard length 'tommy' bar you will never over tighten it. If you can get a torque wrench that would be useful.
For the A65 the clutch centre nut is tightened to 70/75 ft/lbs which is quite a lot.
Unless someone comes up with and official setting then perhaps you could settle on 60 ft/lbs.

Dave.

I really can't recall how the clutch plates fit back in.

Do I start with a metal plate or friction plate?
(And does the lip on the metal plate protrude inwards, towards the engine or outwards?)

Thanks again

[DAVE BRADY]

Hi,

If out refer to the drawing posted above, you will see that the clutch drum/basket has friction inserts so start with a plain plate and then a friction plate until they are all fitted.

In the drawing it shows the 'lip' outwards.

Dave.

[ducati2242]

your clutch drum seems to have a steel plate at the back of it so i wouldn't be too sure of copying the drawing you my have to start with a cork plate . remember the steel plates need cork plates either side of them the last one dosent matter as the pressure plate can act as a steel . Or it could be that there is already a plate in their .

[neil1964]

That basket looks to have a complete friction ring, not steel.
An interesting pattern part.
The article I linked to shows how to set the springs.
Check the springs are of the correct length for your number of plates, decent springs with good plates ideally adjusted with a dial gauge to get even lift is invaluable.

[Fraz]

Hi,

If out refer to the drawing posted above, you will see that the clutch drum/basket has friction inserts so start with a plain plate and then a friction plate until they are all fitted.

In the drawing it shows the 'lip' outwards.

Dave.

Thanks again.
I wasn't certain, especially about the lip on the diagram.

Job for tomorrow, rebuild & test the clutch

[Steve.S]

I hope I'm not leading you up the garden path here. I don't know much about these modern BSA's.
What is that ghastly looking mangled steel ring in the clutch hub? I suggest you remove it. There does seem to be some sort of "ring" here, probably as part of the hub, but it looks narrower than yours, and without a large chunk taken out of it. I imagine it's there to try to stop oil getting into the clutch. Maybe someone could post a picture of an original clutch hub?
In pictures 4 and 5, it looks to me that there is a grey friction disc fitted, with a beige friction disc fitted behind it.
According to the diagram, this is incorrect. Your clutch drum and the clutch discs should have friction inserts fitted into them. There are no friction "rings" fitted. These are only fitted on much earlier clutches.
Perhaps someone more knowledgeable than me can comment on the above?
 

[Fraz]

I hope I'm not leading you up the garden path here. I don't know much about these modern BSA's.
What is that ghastly looking mangled steel ring in the clutch hub? I suggest you remove it. There does seem to be some sort of "ring" here, probably as part of the hub, but it looks narrower than yours, and without a large chunk taken out of it. I imagine it's there to try to stop oil getting into the clutch. Maybe someone could post a picture of an original clutch hub?
In pictures 4 and 5, it looks to me that there is a grey friction disc fitted, with a beige friction disc fitted behind it.
According to the diagram, this is incorrect. Your clutch drum and the clutch discs should have friction inserts fitted into them. There are no friction "rings" fitted. These are only fitted on much earlier clutches.
Perhaps someone more knowledgeable than me can comment on the above?
 

Do you mean the thin metal ring that runs around the inside of the inner clutch basket? (Can't add another photo)

[Fraz]

Hi,

Before fitting any plates put the washer and domed nut on.  Just do it tight rather than torqued up.
The centre should rotate quite feely as it turns the main shaft of the gear box.  Likewise, unless you have the primary chain on, the chain wheel should rotate freely.  These two parts should not touch in any way.

Dave.

Hi.
I've done as you suggest.

Inner basket, then a new tab washer, then the domed nut.
Tightened up (not torqued)
Primary chain removed

Centre clutch basket is "locked" to the outer / primary chain sprocket and that won't turn without turning the back wheel.

If the centre basket should spin freely without contacting the outer basket, then there's something really wrong here.

I've no idea