Author Topic: A7 Fork Rebuild  (Read 200 times)

Offline Craig

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A7 Fork Rebuild
« on: 08.07. 2019 00:58 »
Morning All

Am currently rebuilding the forks on my '49 A7 (longstroke engine) and need to replace the stanchions. they are in pretty bad shape (slightly bent)  and lots of pitting in the chrome.

As usual lots of conflicting information on the web about which parts are correct replacement so wanted to see if anyone here had bought replacements and which were correct.

The current stanchions are 22 1/2" long and have 1 hole in them. From what I read these are fine to replace with new stanchions of same length even with 2 holes. The new top bushes are longer than original but that is no problem either.

Is correct replacement part number - 42-5027?
https://www.classicbikeshop.co.uk/bsa-gold-star-hard-chrome-fork-stanchions-42-5027.html

I also see 89-5061 - but as far as i can see there is no difference? (just need to add the bushes)
https://www.classicbikeshop.co.uk/bsa-fork-stanchions.html

Appreciate any advice or notes from your experience before making a purchase.

Thanks

Craig







Online morris

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Re: A7 Fork Rebuild
« Reply #1 on: 11.07. 2019 22:28 »
22 1/2 89-5061 is the right length. There’s two types, long and short ones. I think the short ones are for the A65 1963. After that they went to long again but then have more oil holes
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Online duTch

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Re: A7 Fork Rebuild
« Reply #2 on: 12.07. 2019 10:28 »

 The difference I see are the first ones are complete with bushes and the others have no bushes
Started building in about 1977/8 a on average '52 A10 -built from bits 'n pieces never resto intended -maybe 'personalised'
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Online chaterlea25

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Re: A7 Fork Rebuild
« Reply #3 on: 12.07. 2019 20:45 »
Hi Craig,
The original stanchions with one oil hole were shorter than those currently available, they were fitted with shorter top bushes to compensate for the leg length difference
Or vice versa the longer legs and longer bushes work out at the same fitted length
The advantage of the two hole stanchions are that on extension oil is trapped in the space between the bushes
stopping the topping out metal to metal clashing that can happen with the one hole type legs

So fit the new longer legs and bushes and look forward to improved fork action

John

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