Author Topic: six spring clutch  (Read 2007 times)

Offline bonny

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six spring clutch
« on: 04.08. 2010 00:40 »
the clutch fitted to my a10 is the 6 spring variety , is it as bad as its reputation suggests ? i only rode the bike a few miles before pulling it down to rebuild it, but i didn't notice anything the matter with it , also where can i get the correct handlebar lever for the clutch ? something i read about 1 1/16" as oppossed to 7/8" or something like that.

any tips on how to set it up welcome.

Offline Brian

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Re: six spring clutch
« Reply #1 on: 04.08. 2010 02:23 »
When you say six spring I take it you mean the six spring in a swingarm model.

These clutches are not the best design BSA came up with but can be made to work quite well. All the usual stuff applies, good condition, quality plates etc. There is a better bearing available for these now, instead of the two rows of balls being held in little cages they are held in a alloy ring with a hole for each ball. I fitted one of these to one of my bikes and it does seem to be better. C@D's sell them and probably others.

If it worked well before you dismantled the bike then all should be well.

Offline bonny

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Re: six spring clutch
« Reply #2 on: 04.08. 2010 03:01 »
yes i should have said , its a 1958 swingarm machine .

Offline BSA_54A10

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Re: six spring clutch
« Reply #3 on: 04.08. 2010 11:33 »
The 6 spring clutch is an example of what you get out is proportional to what you put in.
I know owners who set their's up using dial gauge and they run very sweet indeed.
Others who "shot it together" seem to have no end of trouble and derride it all the time.

I am running a 6 springer in the M20 at the moment while the single spring is being rebanded and it is not giving me any grief.

You must take great care to get the pressure plate lifting squarely ( hence the dial gauges )
I cheat and use a top hat lifter so it always lifts square ( well almost square ).
Also the pivot in the gearbox outer must be in good condition.
If the hole is oval then get it bushed.
Same goes for the pivot on the handle bar and the lever itself.

You only need to get the clutch just tight enough not to slip.
The text book method has it too tight.
I set mine so that the engine just stalls if the clutch is let out  with the bike in top gear and the front wheel against a brick wall and in my case that is nearly 2 full turns lighter than BSA recommends.
Bike Beesa
Trevor

Offline bonny

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Re: six spring clutch
« Reply #4 on: 04.08. 2010 18:36 »
thanks trevor , i'll persevere with it so , i don't want to waste a good item if its serviceable.

Offline trevinoz

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Re: six spring clutch
« Reply #5 on: 04.08. 2010 23:16 »
Bonny,
            If you can select first while standing still without a hell of a crunch and lurch, and can select neutral easily when stopped, your clutch is good.
Trev.

Offline bonny

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Re: six spring clutch
« Reply #6 on: 05.08. 2010 00:35 »
Bonny,
            If you can select first while standing still without a hell of a crunch and lurch, and can select neutral easily when stopped, your clutch is good.
Trev.

it was ok before i removed it , so it must be in reasonable condition , all the plates are new and everything seems to be in fine shape.

Offline Goldy

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Re: six spring clutch
« Reply #7 on: 05.08. 2010 16:53 »
As others have said it's very important to get the outer plate to pull off square. I use a caliper type depth guage positioned on four points around the edge of the chain wheel. Keep adjusting the nuts until the plate is completely square. Just takes a bit of time.
56 A10 Golden Flash - Restore, ride, relive.                                          
56 C12 BSA project ongoing

Offline BSA_54A10

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Re: six spring clutch
« Reply #8 on: 06.08. 2010 01:56 »
It is worthwhile to ferret around aftermarket shops and auto jumbles to find a top hat lifter.
It replaces the pin in the middle of the pressure plate with a steel flanged bush.
A radial roller bearing runs on the flange and a flanged lifter with a stem that that locates into the bush with the other end about 1" or more down the main shaft .
They used to be quite common a few years back but I have not seen them around for a while.

Bike Beesa
Trevor

Offline bonny

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Re: six spring clutch
« Reply #9 on: 06.08. 2010 02:13 »
i suppose no one makes the alloy pressure plate like the one for the 3 and 4 spring units ?

Offline A10Boy

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Re: six spring clutch
« Reply #10 on: 06.08. 2010 09:39 »
I fitted an SRM ally pressure plate, pushrod, springs and cups to my four spring clutch. It now like a japanese clutch, I can even select neutral at standstill and its as light as a feather.   *smile*

Not sure they do one for a 6 springer.

Regards

Andy

1958 Super Rocket
Plus
Harley Super Glide Custom
Yam XJR 1300