BSA Owners' Club Workshop Discussions

The BSA Workshop => Twins => Topic started by: Mike Farmer on 18 Apr, 2018, 10:09

Title: A65 Fork shafts
Post by: Mike Farmer on 18 Apr, 2018, 10:09
 :)

Good morning to all.

The A65 I'm working on has some seriously poorly fork shafts/stanchions. As I see it there were three types made and used over the years and I want to be certain what I buy is correct.

I know that they are not the last ones. Now my question is---are the other two interchangeable. Cos my real problem is that I don't know the actual year of the forks only the probable year.

I've just been looking at Draganfly diagrams and that doesn't fully answer the question.

Your advice seriously appreciated.

Mike 8) 8)
Title: Re: A65 Fork shafts
Post by: JulianS on 18 Apr, 2018, 11:25
Mike

There were 5 types;

1962-65 full width hub, shorter version of A10 shafts.

1964-65 half width hub type for sports models - A50 Cyclone, A65 Lightning Rocket and Spitfire Hornet - which took the A10 shaft.

1966-1968 type with 2 way damping , damper assembly fixed to fork bottom with a socket cap screw.(These are noticable with a ring of oil holes drilled around the bottom diameter)

1969/70 shuttle valve type.

Finally the OIF type.

What you need will depend on the fork bottoms you have.
Title: Re: A65 Fork shafts
Post by: Mike Farmer on 18 Apr, 2018, 14:54
 :)

Thanks for that now I am at least looking in the right direction.

Mike 8)
Title: Re: A65 Fork shafts
Post by: Mike Farmer on 20 Apr, 2018, 14:11
 :) Hi Julian.
Picking up on the fork shafts___This the info from Draganfly parts lists.

My sliders are42-5141/42 (1962/63 pattern)

The shafts for mine come up as 60-5030.

The bushes come up as 65-5424 and 29-5347 (These same bushes are used with shafts 68-5144)

Does that mean that the shafts are interchangeable.

Its no big deal but I would be very interested in your thoughts.

Thanks Mike 8) 8)
Title: Re: A65 Fork shafts
Post by: JulianS on 20 Apr, 2018, 14:42
No it does not.

68 5030 is 21 1/8 inch long and is used with the dropped top yoke and no damper rod.

68 5144 is 22 5/8 inch long and is for use with damper rods and non dropped top yoke. It has larger oil transfer holes drill around the shaft just above the bottom bush.

Yes they take the same bushes.

The geometry is different. The damping arrangements different.
Title: Re: A65 Fork shafts
Post by: Mike Farmer on 20 Apr, 2018, 18:59
 :) :)

Thank you. I was just curious about the detail.

Mike 8) 8)
Title: Re: A65 Fork shafts
Post by: MITCHELL on 20 Apr, 2018, 20:47
Hi Mike, I don't know if it would help but I've got my forks played out on a bench at the moment, there of a 1964 a 65, I could take some photos and mail them to you if you want.
Title: Re: A65 Fork shafts
Post by: Mike Farmer on 21 Apr, 2018, 08:22
 :) :)
Hi thanks for the offer and I would appreciate that very much. I think I know where I am with this but every little helps. PM to you with email address.
Mike 8)
Title: Re: A65 Fork shafts
Post by: Mike Farmer on 26 Apr, 2018, 20:01
 :)
Hi All.

I now have my new fork shafts and await the arrival of new bushes. I have not done this particular job for several moons (The only other  time 1957 I think)
Any tips viz fitting the bottom bush would be appreciated.

Mike 8) 8)