Author Topic: Clutch adjusting  (Read 2854 times)

Offline RoyC

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Clutch adjusting
« on: 27.11. 2017 08:35 »
6 spring.
I know that I have to check that the clutch is lifting evenly but how do I tell how much to compress the springs ?
At the moment the nuts are at the top of the adjustment (springs under least compression)
Thanks
Roy.
My bike is a 1958 A7SS
Staffordshire UK

Offline RoyC

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Re: Clutch adjusting
« Reply #1 on: 27.11. 2017 10:11 »
I have found the answer to my question in the service sheets book.

Roy.
My bike is a 1958 A7SS
Staffordshire UK

Offline BSA_54A10

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Re: Clutch adjusting
« Reply #2 on: 27.11. 2017 21:57 »
Ignore the service sheets,
They will have the clutch way too tight.
Starting with the nuts at the end of the bolts screw them down an equal number of turns till the clutch does not slip, bike in gear, front wheel against a wall when you STAND on the kick starter.
From this point , adjust the nuts in or out as needed to get the plates to lift square.
Once there back off each nut 1/6th turn till the clutch just slips when tested as per above.
From there tighten each one 1/2 to 1 full turn.
Start the bike, put it in gear then let the clutch out slowly.
If the bike does not stall tighten the nuts evenly in 1/6th turns till it does.

You are aiming for the LIGHTEST clutch you can get and the lighter the better.
Factory settings give you a clutch that will not slip, but usually is way way way too heavy thus flogging out the lever pivots and straining your wrists.
When done correctly you should be able to pull the lever in with 2 or 3 fingers.
Bike Beesa
Trevor

Offline RoyC

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Re: Clutch adjusting
« Reply #3 on: 29.11. 2017 14:31 »
Thank you for that Trevor.
I got myself a dial gauge to set the clutch up.
When the clutch is fully engaged there is a 3mm runout (+ / -  1.5mm).
When the clutch is fully disengaged (Lever pulled in) there is no runout at all.
Someone did a remarkable job of setting it up prior to my ownership.
Does that 3mm runout matter with the clutch engaged ?
Roy.
My bike is a 1958 A7SS
Staffordshire UK

Offline BSA_54A10

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Re: Clutch adjusting
« Reply #4 on: 30.11. 2017 06:34 »
Yes.
Usually you will find the thick plate behind the basket is bent.
Bike Beesa
Trevor

Offline RoyC

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Re: Clutch adjusting
« Reply #5 on: 30.11. 2017 08:22 »
Yes.
Usually you will find the thick plate behind the basket is bent.
Does that effect the working of the clutch ?
My bike is a 1958 A7SS
Staffordshire UK

Offline JulianS

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Re: Clutch adjusting
« Reply #6 on: 30.11. 2017 09:49 »
Roy - all the parts need to be really good condition. The 6 spring swinging arm clutch has a bad reputation for drag, slip and heavy action so you need all the help you can get.

Offline RoyC

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Re: Clutch adjusting
« Reply #7 on: 30.11. 2017 16:34 »
Roy - all the parts need to be really good condition. The 6 spring swinging arm clutch has a bad reputation for drag, slip and heavy action so you need all the help you can get.
Thanks Julian, I think I need a complete new clutch.
Roy.
My bike is a 1958 A7SS
Staffordshire UK

Offline JulianS

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Re: Clutch adjusting
« Reply #8 on: 30.11. 2017 17:45 »
Roy

I would consider using a 4 spring type - better all around than the 6 spring swinging arm one - lighter to use and easier to keep in adjustment compared to the 6 spring.

Offline RoyC

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Re: Clutch adjusting
« Reply #9 on: 30.11. 2017 18:25 »
Roy

I would consider using a 4 spring type - better all around than the 6 spring swinging arm one - lighter to use and easier to keep in adjustment compared to the 6 spring.
1.  Would this do the job ?  -  https://www.ebay.co.uk/itm/BSA-A10-Goldstar-4-Spring-Clutch-Complete-NEW/132340673257?hash=item1ed01e6ae9:g:7EUAAOSwtpZYSU5A 
2.  Do they all have the same number of gear teeth ?
3.  Do I need anything else ?
4.  Would the 4 spring be strong enough to pull the sidecar ?

Roy.
My bike is a 1958 A7SS
Staffordshire UK

Offline a10gf

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Re: Clutch adjusting
« Reply #10 on: 30.11. 2017 19:05 »
Out of curiosity, got very good experience with the 6 spring on the plunger (once well adjusted and internals in good shape), why is (what parts makes) the swingarm 6 spring seemingly troublesome ?

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Online Billybream

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Re: Clutch adjusting
« Reply #11 on: 30.11. 2017 19:19 »
Hi Roy.
If you want to go for the 4 spring version I would pay a little extra and go for the SRM unit.
Includes machined alloy clutch cover with needle roller arrangement. The EBay unit still appears to use the steel pressed cover without the needle roller.
Also you should consider cutting the actuating push rod and inserting a ball bearing.
1960 Super Rocket, owned since 1966, back on the road 2012 after being laid up for 29yrs.

Offline RoyC

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Re: Clutch adjusting
« Reply #12 on: 30.11. 2017 19:30 »
Hi Roy.

Also you should consider cutting the actuating push rod and inserting a ball bearing.

Why ?
My bike is a 1958 A7SS
Staffordshire UK

Online Billybream

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Re: Clutch adjusting
« Reply #13 on: 30.11. 2017 20:03 »
Cutting the clutch push rod and inserting a ball bearing reduces fiction and improves clutch operation.
1960 Super Rocket, owned since 1966, back on the road 2012 after being laid up for 29yrs.

Offline RoyC

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Re: Clutch adjusting
« Reply #14 on: 30.11. 2017 20:23 »
Cutting the clutch push rod and inserting a ball bearing reduces fiction and improves clutch operation.

Right. Does it have to be cut in the middle and have the diameter of the ball bearing removed from the length so that the rod is still the same length as when it was solid?
My bike is a 1958 A7SS
Staffordshire UK