Author Topic: A10swing arm identification  (Read 3035 times)

Offline Plammimam

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A10swing arm identification
« on: 24.10. 2018 20:01 »
Hi All
I am working my A10 Spitfire replica. I need some help identifying the swing arm fitted. It looks like the swing arm has had the chain guard lugs added on the left side and the plate for a left hand rod half width brake torque arm added. I can’t seem to get the right spacers for the rear wheel. The 67-6028 is too long for the half width crinkle hub set up.
Biggest conundrum is the right lug where the axle goes through is 1.00 inch, see the picture. I can’t seem to find either a spindle that size or any bushes to pack out.
Any clues would be appreciated
Phil

Offline chaterlea25

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Re: A10swing arm identification
« Reply #1 on: 24.10. 2018 21:06 »
Hi Phil,
There are 3 types of swing arm,
Crinkle hub, Ariel hub and the cast iron full width.
Early swing arm twin or single swing arms use a smaller diameter pivot spindle

One of the "Gold Star" swing arms which is the same as early B31/33 and A7/10 went for £374.02 on eBay last week *eek* *eek* *eek*
https://www.ebay.ie/itm/BSA-Original-Swinging-Arm-A10-A7-B31-B33-Goldstar-QD-Excellent-condition-Swing/323493242315?ssPageName=STRK%3AMEBIDX%3AIT&_trksid=p2060353.m1438.l2649

Spacers to adapt one wheel to another swing arm will have to be "engineered" not bought

John
1961 Super Rocket
1963 RGS (ongoing)

Online morris

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Re: A10swing arm identification
« Reply #2 on: 24.10. 2018 21:56 »
A plunger crinkle hub shaft is 1” so might fit your setup ?
'58 BSA A 10 SA
'52 BSA A 10 Plunger
'55 MORRIS ISIS
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Online berger

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Re: A10swing arm identification
« Reply #3 on: 24.10. 2018 22:43 »
i have not been to the pub, blinkin ek that swing arm is same as mine and many more, I know what to do when I run out of beer vouchers *work* *beer* *whistle*

Offline Plammimam

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Re: A10swing arm identification
« Reply #4 on: 24.10. 2018 23:11 »
Hi John
The swing arm on eBay looks the same as my one, but I can’t tell the size of the right axle slot to be sure. The distance between the lugs across the arm is 7 inches. There is a comment from Berger that a plunger crinkle hub takes a 1inch axle, wouldn’t that mean bearing changes to suit?
Phil

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Re: A10swing arm identification
« Reply #5 on: 24.10. 2018 23:29 »
nowt to do we me that was morris , I will try and av a butchers at mine and do a bit of measuring and report back. I can't do piccies tho even if you lourve them

Offline chaterlea25

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Re: A10swing arm identification
« Reply #6 on: 24.10. 2018 23:31 »
Hi Phil
If I think of it I can measure a crinkle hub swing arm spindle slot tomorrow

John
1961 Super Rocket
1963 RGS (ongoing)

Online morris

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Re: A10swing arm identification
« Reply #7 on: 25.10. 2018 12:52 »
a plunger crinkle hub takes a 1inch axle, wouldn’t that mean bearing changes to suit?
Phil

Here's a picture from a plunger shaft from the De Groot website
The corresponding bearings are RLS8
'58 BSA A 10 SA
'52 BSA A 10 Plunger
'55 MORRIS ISIS
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Offline Greybeard

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Re: A10swing arm identification
« Reply #8 on: 25.10. 2018 13:12 »
If you need something made up, in SS, I've had good experiences with these chaps: http://www.cpcengineering.co.uk/
I had them make me one of those rear wheel spindles. It was a tad tight on the threads so I mailed it back to them. They eased the threads and speedily sent it back, covering all postage costs. I've recently had some other parts made by them that are splendid. They are a couple of young chaps.
Greybeard (Neil)
2023 Gold Star
Supporter of THE DISTINGUISHED GENTLEMAN'S RIDE https://www.gentlemansride.com

Warwickshire UK


A Distinguished Gentleman Riding his 1955 Plunger Golden Flash

Offline Plammimam

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Re: A10swing arm identification
« Reply #9 on: 25.10. 2018 14:51 »
Thanks for the picture of the plunger spindle and ref to associated bearings. I checked the RLS8 bearings spec and found they have an OD of 2.1/4. Inch. My crinkle hub will only take 2 inch which equates to RLS7.

I suppose the question is what BSA has a swing arm with the right slot at 1 inch

Online morris

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Re: A10swing arm identification
« Reply #10 on: 25.10. 2018 18:19 »
My crinkle hub will only take 2 inch which equates to RLS7.
That’s a pity because it looks like lengthwise the plunger shaft would also fit. The distance between the lugs is 7” also. If nothing else works maybe you could have a plunger shaft turned down to accept the RLS 7 bearing?
'58 BSA A 10 SA
'52 BSA A 10 Plunger
'55 MORRIS ISIS
The world looks better from a motorbike
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Offline harvey mushman

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Re: A10swing arm identification
« Reply #11 on: 25.10. 2018 19:08 »
Thanks for the picture of the plunger spindle and ref to associated bearings. I checked the RLS8 bearings spec and found they have an OD of 2.1/4. Inch. My crinkle hub will only take 2 inch which equates to RLS7.

I suppose the question is what BSA has a swing arm with the right slot at 1 inch

Is the FW Ariel hub not fitted with a 1" spindle diameter?

cheers

derek

Offline Plammimam

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Re: A10swing arm identification
« Reply #12 on: 25.10. 2018 20:44 »
BSA owners club tech section, says swing arm is from a later bike with full width hub. Didn’t say which bike or year, not so helpful. Looks like the easiest option is to make a top hat bush for the spindle to frame lug to eliminate the space and probable make a spacer from wheel to lug same dimension as a plunger spacer but with 7/8 ID.
Anyone know the length of that spacer, bets are on 1.403 or there about
Phil

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Re: A10swing arm identification
« Reply #13 on: 25.10. 2018 21:13 »
Anyone know the length of that spacer, bets are on 1.403 or there about
Phil

1.562 (1 9/16”)
'58 BSA A 10 SA
'52 BSA A 10 Plunger
'55 MORRIS ISIS
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Offline Plammimam

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Re: A10swing arm identification
« Reply #14 on: 25.10. 2018 21:29 »
That’s my problem, the 67-6028 is that length and it’s to long. I need 1.40 with this swing arm and crinckle hub set up with 7 inches lug to lug. I have seen drawings on the net showing lug to lug as 7 15/32 and 7 1/32 for A10 so no consistency