Author Topic: bsa a10 clutch id  (Read 13784 times)

Offline 69Bonni

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Re: bsa a10 clutch id
« Reply #30 on: 26.06. 2009 13:48 »
Hi Guys

Glad she is running ok Sausage! nice there is a way to check the oil levels if you have a primary case with a bolt in the bottom it has an oil level pipe inside this gives you the correct oil level if not it will be one of these ...........

Hi Mike uummm thats very tempting, especially as i will probably have to totally rebuild the clutch anyhow i have seen complete clutches new for about 280 probably not much more for a Belt drive.

Richie, Take a took at BBB page http://www.burtonbikebits.net/alloy_clutch_drums.htm at the bottom you will see the A65 and T140 3 spring clutches i cant see the difference. It may be that its a Duplex or Triplex chain my A65 is Triplex, i suspect you have a Single chain version of this clutch basket, yes all the clutch plates are interchangable!

Cheers

Steve
Kind Regards
Steve Rickman

Offline beezalex

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Re: bsa a10 clutch id
« Reply #31 on: 26.06. 2009 19:31 »
Looks like they somehow managed to use a 6-spring basket.  The friction plates are definitely interchangeable, but the bearing arrangement would have to be tweaked.
Alex

Too many BSA's


Offline a10sausage

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Re: bsa a10 clutch id
« Reply #32 on: 27.06. 2009 10:50 »
thanks steve for the primary chain case brochure scan...very helpful,hey you never know this 3 spring clutch might even become a popular mod !
1959 bsa bantam d1
1956 ariel huntmaster
1922 triumph model h
1930 sunbeam model 8
1936 bsa q21 500 bluestar
1939 velocette mac
1975 honda cb750
2013 victory vegas

Offline trevinoz

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Re: bsa a10 clutch id
« Reply #33 on: 28.06. 2009 21:43 »
I have done a similar conversion using a three spring centre and pressure plate. The centre has to be modified by fitting a shoulder for the first steel plate to bear against. I silver soldered an old steel plate to the centre and turned it to the correct diameter.
The three spring centre doesn't have a shoulder as the basket has a friction lining for the first plate to bear against.
A bloke I know has modified a basket from the later clutch by machining off the duplex sprocket and fitting a simplex one but he had to use a 44 tooth sprocket as he reckons to fit a 43 tooth type would weaken the basket.
I am still looking into this.
Trev.

Online chaterlea25

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Re: bsa a10 clutch id
« Reply #34 on: 28.06. 2009 22:23 »
Hi All,
There used to be A65 type centres available to fit the A10 box, I dont know if they still are??
this meant that you could fit the A65 thrust washer behind the A10 chain wheel, then either an A65 centre or machine the lip off the four spring centre,
Then fit an extra friction plate into the basket first, this provides a much more solid base for the plates to press against, in the standard setup the inside steel plate is only supported on its inner edge and is able to flex away from the friction plate.
I know on some other motorcycles (including some BSA's) the rearmost plate is double thickness to try and prevent this happening.

The Pearson Suzuki clutch, see
http://archives.jampot.dk/Technical/Transmission/Suzuki_Clutch_conversion.pdf

Lovely clutch, lovely price! *eek*

 *idea* *idea* Having read the article I went out and bought a couple of Suzuki clutches on ebay and am planning to do my own conversion,
I will document it and let you all know how it goes
I have my recently aquired RGS as a test bed, with its RR T2 box it will need a meaty clutch *ex* *ex*

Regards
John O R

1961 Super Rocket
1963 RGS (ongoing)

Offline beezalex

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Re: bsa a10 clutch id
« Reply #35 on: 29.06. 2009 17:46 »
A bloke I know has modified a basket from the later clutch by machining off the duplex sprocket and fitting a simplex one but he had to use a 44 tooth sprocket as he reckons to fit a 43 tooth type would weaken the basket.
I am still looking into this.
Trev.

Interesting.  I'm looking into doing this modification for my Silver Star, which uses the same clutch.  I have come to the same conclusion on the basket...a 43-tooth sprocket would reside too close to the basket and the clutch baskets can't have much machined off them.  Even a 44-tooth is going to be pretty close, but I think going bigger may introduce some clearance issues.  My other thought was possibly using a B50 clutch...much more room around the outside for a 43-tooth sprocket...though it is quite a bit smaller.  Just thinking out loud here...
Alex

Too many BSA's