Author Topic: Clutch adjusting  (Read 2852 times)

Offline RogerSB

  • 1960 Golden Flash, Plymouth, Devon, England
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Re: Clutch adjusting
« Reply #30 on: 01.12. 2017 10:57 »

Your nuts don't seem to be tightened down very much, do they have locking nuts ?
Is that the pad behind the sliding plate that you changed ?

Anyone know what size ball bearing I need to get ?
Roy.


Hi Roy,

In the SRM instructions they say make sure one coil of the springs is showing above the cups or you'll get drag, so I thought I'd try it on two first off and on road testing that was fine - and down here in Plymouth we have lots and lots of steep hills to challenge a slipping clutch.

I did have to shorten my 6 spring pushrod. Like an idiot I didn't measure what I ended up with but if you set the clutch up and adjust the supplied top hat pusher about half way then (as far as I recall you need to shorten the pushrod so that about 1/4" is protruding on the gearbox side. In my first attempt I cut my original pushrod a fraction too short but luckily I'd recently bought a length of 1/4" silver steel for just this purpose so made another from that, which ended up the correct size. Heated the ends to cherry red and quench in oil (I use the old ATF I removed from the chaincase I used with the 6 spring). SRM recommend using SAE 40 and say not to use ATF, I used some Castrol GTX SAE 15/40 that I had.

When the clutch lever is pulled in about half way the arm on the gearbox should be parallel with the cover joint or 90 degrees to the pushrod. When the lever is not pulled it should be approximately at 11 o'clock, so that'll give you an idea of what length your pushrod needs to be. I didn't fit a ball bearing and in my opinion it's not needed with this clutch. Lever is a one finger affair - so why try to change it?

Yes, the felt washer is the big one (about 4" dia ) that is squeezed between the inner case and the sliding plate. SRM also provide a smaller felt washer which fits on the back of the clutch centre and also a copper thrust washer. The tricky bit is carefully offering the chainwheel up to clutch hub and keeping all the twenty bearings in situ (packed in grease). One of those jobs that you could do first attempt or It'll take a couple of attempts but make sure they all stay in place.

The four studs in the centre hub come supplied loose. They have square heads, which fit in a recessed ring in the back of the hub and wobble about a lot (which worried me) but when you fit the cups and springs and when under slight tension they centralise themselves and are firm enough.

The other thing that struck me when adjusting the spring pressure is that this clutch is so easy to successfully set up because of the solid pressure plate and the design of the pusher. Even with the springs under tension you can push on the pressure plate and wobble it from side to side, which to me means that when it's pushed away with the top hat pusher (with its lovely roller bearings) to disengage the plates I think it's sort of self centralising and therefore it's not such a hassle to get it perfect like you do with the dodgy flexible 6 spring version. I maybe wrong but I'm convinced that this pressure plate doesn't need to run 100% true like the 6 spring. I just screwed in the nuts to where I thought I'd try it and bingo!

Anyway, good luck with it, I'm sure like everyone else you'll be delighted.

1960 Golden Flash

Offline RogerSB

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Re: Clutch adjusting
« Reply #31 on: 01.12. 2017 11:19 »
do they have locking nuts ?

Anyone know what size ball bearing I need to get ?
Roy.


Missed the bit about locking nuts Roy, but no locking nuts required. When you get yours take note that the spring cups have indentations in the rims that locate in indentations in the pressure plate to stop them turning. I found the adjusting nuts are easier to turn in to tighten them than out to loosen as you come up against the end of the spring and it needs some force to turn past it - until next time around. You need a tool like the one I bought in photo - or a big screwdriver will do it. Some even use a big screwdriver and file a bit out of the middle but I found if you have a big enough screwdriver it'll do the job.

1960 Golden Flash

Offline RoyC

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Re: Clutch adjusting
« Reply #32 on: 01.12. 2017 11:51 »
do they have locking nuts ?

Anyone know what size ball bearing I need to get ?
Roy.

You need a tool like the one I bought in photo
I've got one of those tools Roger.
Thanks for the other info.
Roy.
My bike is a 1958 A7SS
Staffordshire UK

Offline RoyC

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Re: Clutch adjusting
« Reply #33 on: 01.12. 2017 19:29 »
Do you have to remove the back primary casing to remove the sliding plate, in order to renew the felt pad ?
My bike is a 1958 A7SS
Staffordshire UK

Offline RogerSB

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Re: Clutch adjusting
« Reply #34 on: 01.12. 2017 20:22 »
Hi Roy,
It's easier if you do. The sliding plate is secured by two shouldered bolts, the nuts are behind the inner case. It may be just possible to get a spanner on them. The front one is the easiest, the rear is more difficult.  If you want to change the cush drive nut then it's probably worth doing. Of course it all depends on the condition of your felt seal (whether leaking oil or not).

1960 Golden Flash

Offline RoyC

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Re: Clutch adjusting
« Reply #35 on: 01.12. 2017 20:40 »
Hi Roy,
It's easier if you do. The sliding plate is secured by two shouldered bolts, the nuts are behind the inner case. It may be just possible to get a spanner on them. The front one is the easiest, the rear is more difficult.  If you want to change the cush drive nut then it's probably worth doing. Of course it all depends on the condition of your felt seal (whether leaking oil or not).

I may have a go at removing the inner case. I have ordered a couple of cork gaskets to go between the inner case and crank case. There is a leak somewhere and I may as well cover everything while i'me this far.
I may have trouble getting at the nut/bolt by the rear chain because I have the fully enclosed one.
My bike is a 1958 A7SS
Staffordshire UK

Offline RogerSB

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Re: Clutch adjusting
« Reply #36 on: 01.12. 2017 20:49 »

I may have trouble getting at the nut/bolt by the rear chain because I have the fully enclosed one.


Yes I think you will, as I believe the front part of the chaincase is attached to the inner case.


Don't forget to check the alignment of the engine and chainwheel sprockets. You can get shims for the engine sprocket quite cheaply.

1960 Golden Flash

Offline chaterlea25

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Re: Clutch adjusting
« Reply #37 on: 01.12. 2017 22:53 »
Hi Roy and All,
Quote
I have ordered a couple of cork gaskets to go between the inner case and crank case. There is a leak somewhere and I may as well cover everything while i'me this far.

Cork would not be a good idea for these gasket positions  *sad2*
Cork gaskets will never tighten down solidly, and the thickness will alter the case position enough that it probably
will mean clearance problems with the primary chain and or clutch

With the full  chaincase the bolts holding the sliding plate are longer and also hold the front section of the FERC in place
They are a real pain to get at *problem*

A source of leakage can be from between the two parts of the sliding plate as they are only spot welded in a couple of places, seal around the vee with your favourite sticky goo
I have not had much success with replacement felt seals,  *sad2*
A while ago I bought some oil proof "foam" seals on ebay and they work well

From your posts I gather that you are replacing the 6 spring clutch with SRM's 4 spring unit  *????*
Some time ago I posted about some of the problems encountered when fitting new components to the primary side and getting them to work in harmony
https://www.a7a10.net/forum/index.php?topic=9646.msg70166#msg70166

John


1961 Super Rocket
1963 RGS (ongoing)

Offline RoyC

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Re: Clutch adjusting
« Reply #38 on: 02.12. 2017 07:38 »
Hi Roy and All,
Quote
I have ordered a couple of cork gaskets to go between the inner case and crank case. There is a leak somewhere and I may as well cover everything while i'me this far.

Cork would not be a good idea for these gasket positions  *sad2*
Cork gaskets will never tighten down solidly, and the thickness will alter the case position enough that it probably
will mean clearance problems with the primary chain and or clutch

With the full  chaincase the bolts holding the sliding plate are longer and also hold the front section of the FERC in place
They are a real pain to get at *problem*

A source of leakage can be from between the two parts of the sliding plate as they are only spot welded in a couple of places, seal around the vee with your favourite sticky goo
I have not had much success with replacement felt seals,  *sad2*
A while ago I bought some oil proof "foam" seals on ebay and they work well

From your posts I gather that you are replacing the 6 spring clutch with SRM's 4 spring unit  *????*
Some time ago I posted about some of the problems encountered when fitting new components to the primary side and getting them to work in harmony
https://www.a7a10.net/forum/index.php?topic=9646.msg70166#msg70166

John
Hi John, thank you for that very in depth reply.
I can't find any gaskets, other than cork so will have to make one.
A while ago I bought some oil proof "foam" seals on ebay and they work well
What name did these seals go under ?
My SRM has just arrived (7a.m.)  *smile*

Roy.
My bike is a 1958 A7SS
Staffordshire UK

Offline RoyC

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Re: Clutch adjusting
« Reply #39 on: 02.12. 2017 08:36 »
Well, the instructions for cutting the push rod are for unit construction jobs (measuring from the timing side).
How do you determine what length to cut the push rod on a pre unit bike ?
My bike is a 1958 A7SS
Staffordshire UK

Offline RogerSB

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Re: Clutch adjusting
« Reply #40 on: 02.12. 2017 10:16 »
Roy. my 1960 Golden Flash is pre unit. In my post no 30 in 2nd & 3rd para I explained how I did it. There may be a better & more accurate way that someone will come up with but what I did worked ok for me.


First I set up the clutch to what I thought would be ok, with the top hat pusher adjustment set to about half way and then insert it fully into the pushrod hole. Then insert your uncut pushrod from gearbox side. You'll have to have the cable disconnected from the operating arm to swing it out and also remove the adjuster with the ball bearing in the end to be able to insert the pushrod from that side. Be careful you don't drop the adjuster inside the gearbox or you'll have to take the gearbox outer cover off to find it. When you push the pushrod in you'll probably move the top hat pusher out a bit at the other end so go and gently push it back in, then you can see how much of the pushrod is protruding from the shaft at the gearbox end and it's just a matter of judgement from there. Shortening it a little at a time may be wise if you haven't any replacement. When you've got it right then heat and quench to harden the end you cut.


I've repeated para 2 and 3 again here for you:-

I did have to shorten my 6 spring pushrod. Like an idiot I didn't measure what I ended up with but if you set the clutch up and adjust the supplied top hat pusher about half way then (as far as I recall you need to shorten the pushrod so that about 1/4" is protruding on the gearbox side. In my first attempt I cut my original pushrod a fraction too short but luckily I'd recently bought a length of 1/4" silver steel for just this purpose so made another from that, which ended up the correct size. Heated the ends to cherry red and quench in oil (I use the old ATF I removed from the chaincase I used with the 6 spring). SRM recommend using SAE 40 and say not to use ATF, I used some Castrol GTX SAE 15/40 that I had.

When the clutch lever is pulled in about half way the arm on the gearbox should be parallel with the cover joint or 90 degrees to the pushrod. When the lever is not pulled it should be approximately at 11 o'clock, so that'll give you an idea of what length your pushrod needs to be. I didn't fit a ball bearing and in my opinion it's not needed with this clutch. Lever is a one finger affair - so why try to change it?

1960 Golden Flash

Online ellis

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Re: Clutch adjusting
« Reply #41 on: 02.12. 2017 10:46 »
Hi RoyC,

What you want for your sliding plate seal is one from Dave Flintoft engineering. This comes with full instructions on how to fit it. I put one on my A10 swing arm two years ago and not one drop of oil has leaked out.  *smiley4*
 Tel 01287-638677 or email david-flintoft@sky.com   

Offline RogerSB

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Re: Clutch adjusting
« Reply #42 on: 02.12. 2017 11:07 »
Just to add: To check the length of the pushrod you'll need to fit the gearbox side adjuster each time, when you screw it in set its adjustment about half way. Get the end of the top hat pusher and the ball bearing in adjuster on the the gearbox side just lightly touching each end of the pushrod. I found pushing the rod through to the clutch side and then by gently pushing in the top hat pusher while looking over the bike to the gearbox side you can see the moment the pushrod starts to move the actuating arm. The actuating arm should have been moved to about 11 o'clock to gearbox outer cover joint. That will show the pushrod is an acceptable length. With the clutch lever pulled in about half way you will see that the top hat pusher will have moved out and the actuating arm should now be parallel with gearbox cover joint. Slacken off the clutch pressure plate central adjuster and fit the clutch pressure plate and adjust the springs. when this is done the necessary free play can be done with a combination of both the gearbox side adjuster and the top hat pusher adjuster in the centre of the pressure plate and finally at the lever.


As I said previously this was the method I used, there may be a better way and if there is I'm sure someone will tell you.

1960 Golden Flash

Offline RoyC

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Re: Clutch adjusting
« Reply #43 on: 02.12. 2017 11:58 »
Hi RoyC,

What you want for your sliding plate seal is one from Dave Flintoft engineering. This comes with full instructions on how to fit it. I put one on my A10 swing arm two years ago and not one drop of oil has leaked out.  *smiley4*
 Tel 01287-638677 or email david-flintoft@sky.com   
Thanks for that, I have sent him an email.
My bike is a 1958 A7SS
Staffordshire UK

Offline RoyC

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Re: Clutch adjusting
« Reply #44 on: 02.12. 2017 12:08 »
There has been a new development.
The push rod that is fitted has a ball bearing with dimples in the end of the rods to match.

I have got the clutch partly dismantled (plates out, nut off) but can't budge the inner basket with the 6 bolts sticking out, I thought that it would just pull out.

Roy.
My bike is a 1958 A7SS
Staffordshire UK