BSA Owners' Club Workshop Discussions

The BSA Workshop => Singles => Topic started by: Stubaker58 on 19 Jan, 2025, 17:25

Title: Footrest bolt C15/B40
Post by: Stubaker58 on 19 Jan, 2025, 17:25
Hi,
Finally getting started on building up the bicycle on my B40 having completed the engine.
Can anyone tell me what size the bolt for the offside riders footrest should be? The usual sources have let me down😕
Part number 40-4809
Thanks
Title: Re: Footrest bolt C15/B40
Post by: rhyatt on 19 Jan, 2025, 17:49
https://draganfly.co.uk/shop/65245/footrest-bolt-1596622428/#40-4809

https://draganfly.co.uk/shop/65244/footrest-nut-lh-thread/#40-4808

Nut and bolt LH thread
Title: Re: Footrest bolt C15/B40
Post by: V500 on 19 Jan, 2025, 18:59
That's interesting. Recently I found the NOS stud that I meant to fit to my early B40, and as I recall it's double-ended (ie threaded both ends) and it has a serrated section on the middle to allow for footrest height adjustment.
Was this the wrong component supplied all those years ago or did the design change?
Title: Re: Footrest bolt C15/B40
Post by: hoogerbooger on 19 Jan, 2025, 19:11
Should it help...as mine is off ( 65 B40)

( V500 : the one you describe sounds like the nearside stud)

Title: Re: Footrest bolt C15/B40
Post by: Stubaker58 on 19 Jan, 2025, 20:12
Thanks guys,
That didn't take long!
Definitely a left hand thread then?
Title: Re: Footrest bolt C15/B40
Post by: V500 on 19 Jan, 2025, 21:16
Quote from: hoogerbooger on 19 Jan, 2025, 19:11 ( V500 : the one you describe sounds like the nearside stud)

That would explain it. ;)
Title: Re: Footrest bolt C15/B40
Post by: iansoady on 20 Jan, 2025, 10:20
Hoogerbooger - why not use the button on the calipers and measure in inches? It's almost certainly 3/8" (0.375").
Title: Re: Footrest bolt C15/B40
Post by: hoogerbooger on 20 Jan, 2025, 12:04
Quote from: iansoady on 20 Jan, 2025, 10:20 Hoogerbooger - why not use the button on the calipers and measure in inches? It's almost certainly 3/8" (0.375").

Because:
a) decimalistion of inches makes little difference to my SI head and I have to use a look up table either way
b) in 6 year of use I've never noticed that button!

But when I do push it = 0.371"

And bolt just over 3" long of with 1/4" is the head
Title: Re: Footrest bolt C15/B40
Post by: scifi on 20 Jan, 2025, 20:23
It's a BSA...  They only used fractions of an inch...  Decimals and Metric were a long way in the future...

However it is strange that the Spark-Plugs were either 18 or 14 mm.
Title: Re: Footrest bolt C15/B40
Post by: idie on 20 Jan, 2025, 22:11
Spark plugs built by a French man and mass produced by Bosch a German company. Both using the metric system.
Title: Re: Footrest bolt C15/B40
Post by: Stubaker58 on 21 Jan, 2025, 15:11
I've got the nut, bolt and washers on order from C&D Autos, along with a couple of other bits for the B40 and the Bantam.

Thanks everyone.