The BSA A7-A10 Forum

Bikes, Pictures, Stories & more => Chat, Offtopic, Meetings & Everything Else => Topic started by: kiwipom on 23.10. 2017 03:50

Title: What Crank ?
Post by: kiwipom on 23.10. 2017 03:50
hi guys, had this crank sitting on my bench for years i want to get rid of it. I got it with parts when i got my A10 so i`m thinking that it could be A7 or not.  can any one identify it as it may be useful to someone if it is an A7.
 In my opinion it is not in terrific condition but may clean up if the ends are not to far gone. i will put pics in 2 posts, cheers
Title: Re: What Crank ?
Post by: kiwipom on 23.10. 2017 03:52
More pics.
Title: Re: What Crank ?
Post by: Klaus on 23.10. 2017 04:10
The only differece between SJ A10 and A7 after 1950 is the stroke. For identify the crank you had to messure the stroke A7 is 72.6mm
A7 till 1950 are the same as A10 with 84 stroke.
Title: Re: What Crank ?
Post by: kiwipom on 23.10. 2017 05:05
Hi klaus, thanks for that I will did out an A10 crank to compare, cheers
Title: Re: What Crank ?
Post by: JulianS on 23.10. 2017 09:23
Looks like A7 long stroke crank 82mm stroke.

Long stroke engine was 3.374 iches between bore centres, A10 and short stroke A7 3.5 inches between bore centres.