Problems with new 4 spring clutch after recently fitting

[BSA Biker]

Hi all, yes I know I don't contribute often and only when help iS needed, for that please accept my apologies. However once agin I need some help/advice on how to proceed.
Living in Spain has problems getting parts for my 1960 A7 Shooting Star, okay before Brexit but now things 'get lost' in the post or there are incorrect overcharging for import duty.
So back at Easter this year on returning to the UK for a holiday I bought a 4 spring clutch assembly to replace the original (changed many times) 6 spring type from my friend Ray Fisher at Britbits in Christchurch.

After finally fitting it the take up was right at the end of the lever play, although my old 6 spring version was in a normal position on the lever. Also the old clutch actuating pin that goes thru the gear spline was too short and luckily the new one after slightly reducing it in length was okay.

Any suggestions as to how to get the take up at the correct position on the clutch lever please.

[RogerSB]

Here's the notes I made for adjusting the clutch arm at the gearbox. Hope it's what you need. Part numbers are for swinging arm A7 & A10. Picture (double click to enlarge) and .pdf file

Rog.

Edit: If you can't get this adjustment you need to remove gearbox outer cover and move the adjusting lever on it's splines.

[berger]

has it got the correct springs, or you could try it after tightening the springs a bit

[BSA Biker]

Sorry I've tried both those options without any luck so far.
Even tried really screwing the first set of springs down tight, had a job to remove them after getting new ones from Only British Spares in Austria. No import tax from a fellow EU country, just expensive.

[RogerSB]

Are you sure the pushrod is the correct length, as it's critical for correct adjustment.

To do this remove the clutch pressure plate but leave the clutch plates in position.  From the gearbox side push the pushrod through the mainshaft until flush with the end of the shaft on that side. Note how much protrudes out of the shaft at the other end. With it like that offer the pressure plate up and push it against the clutch plates so it pushes the pushrod in through the mainshaft. From the gearbox side note how much is now protruding on that side.

Adjust its length so it just touches the ball (which should be free to rotate) in the end of the adjusting lever when it’s adjusted to about half way along the threads and with the clutch operating arm angle very slightly before 90 degrees to the cable (see drawing). If the pushrod is too long you’ll need to slacken off the adjusting lever fully by its threads or you can remove it to allow the pushrod to move fully through the shaft. Check it’s still just touching the pressure plate at the other end to now be able to determine what length the pushrod needs to be.

I believe for a 4-spring about 11 7/8” isn’t far off and there is some fine adjustment in the threaded adjusting lever.  Of course this is dependant on the rest of the clutch assembly being correct.

Others may have a better, more accurate method but this will at least give you something to work on.

Don't forget to harden the ends of the pushrod.

Rog.

[BagONails]

Not withstanding all the good advice submitted thus far, can I ask the following preliminary questions Mr Biker?

Is everything in the system set correctly for clearances etc. From the clutch lever down to the gearbox end? i.e. 1/8" slack in the cable.
Is the cable in good nick, inner and outer with no lost movement and all moving freely?
Have you got the correct lever ratio at the handlebars?

You mentioned the clutch gripping/coming in at the end of travel, is it clearing fully when you pull in the lever and at what point in the travel does it declutch?
Can you select gears OK and get into 1st at a standstill without a big crunch?

Finally from my experience of renewing a clutch, it felt very fierce and all seemed to come in in a rush when I first rode with it but after a 1000 miles or so it became a lot more progressive and nice to use. I only adjusted the springs to the minimum preload and have not needed to touch anything since with no sign of slip or grab.

I did fit a 1/4" ball bearing in the middle of the push rod after trimming the length down a tad too much, not sure if this made any difference to anything other than the length though.

[raindodger]

My 4 spring is exactly the same, take up at the end of lever travel.  However, it frees completely and doesn't slip.
I put it down to the plates being completely flat, the previous 6 spring plates were definately not.
Tim.

[JulianS]

Check the handlebar lever - they come with pivot to centre of nipple dimensions of 7/8 inch and 1 1/16 inch.

The 7/8 lever gives a lighter more progressive clutch action and is usually found on the later bikes with 4 spring clutch as a standard fitment. Can drag if the plates not flat and/or springs not evenly adjusted.

The 1 1/16 lever gives a heavier action with a more sudden take up.

[BSA Biker]

Looks like both Raindodger and me have the same problem, yes my clutch arm at the gearbox is set at about right angle with a slight gap at the lever for stopping wear on the spindle which is about 117/8" long.
So not sure what it can be. Probably going to have to live with it.

[RogerSB]

Look here, especially Reply 145. Now it's been mentioned . . . I remembered it. 

https://www.a7a10.net/forum/index.php?topic=13099.msg145340#msg145340

Rog.

[chaterlea25]

Hi All,
I fitted a new solid clutch hub, modified the basket so a friction plate sat against the back face plus a 7 plate conversion
The clutch centre has a thrust washer per A65
At first the take up was fierce, maybe I should have oiled the plates? Anyway after about 1000 miles it has improved hugely.. no slip and easy to find neutral
I would put some miles on the bike and I am sure it will improve

John

[BSA Biker]

Yesterday I reduced the length of the rod by 1/8" to 113/4" Today having done a 56 mile test ride it does seem a little better on the clutch lever (which incidentally is 1&1/16" type) but not by much. Will leave it now to wear in and see how things are after some more miles.

Thanks to all for your help and information.