« previous next »
Pages: [1]   Go Down

Author Topic: BSA B31, front wheel spindle  (Read 1695 times)

Offline Johannes

  • Active
  • *
  • Join Date: Aug 2013
  • Posts: 13
  • Karma: 0
BSA B31, front wheel spindle
« on: 26.08. 2013 21:03 »
Hello,

My name is Johannes and I am a new member of this amazing forum. I started to restore a B31 from 1953 and I have a problem!
The thread in the sliding tube of the fork is slightly damaged and has to recuted. I measured the size of the front wheel spindle but it is not so easy. I believe it is a 9/16-20LH thread. I looked for a tap a figured out it is common for bicycle pedals. I borrow a tap from a bicycle dealer. However, the tap started to clamp after 2 rotations and I stopped. Now I am not sure whether it is due to the condition of the thread or the size is wrong.
I would appreciate if somebody can tell me the right size.

Regards
Johannes
Logged

Offline a10 gf

  • Global Moderator
  • Wise & Enlightened
  • **
  • Join Date: Sep 2006
  • Posts: 3287
  • Karma: 58
  • West Coast, Norway & Alpes Maritimes, France
    • A10 GF
Re: BSA B31, front wheel spindle
« Reply #1 on: 26.08. 2013 22:46 »
Hello, and welcome to the forum. You may get some help here for your B, but this is 99,5% an A7A10 place, and we'll be there to help when you buy yourself a twin!
Logged


Stand with
A10 GF '53 My A10 website
"Success only gets you a ticket to a much more difficult task"

Online muskrat

  • Global Moderator
  • Wise & Enlightened
  • **
  • Join Date: Jul 2009
  • Posts: 11477
  • Karma: 137
  • Lithgow NSW Oz
    • Shoalhaven Classic Motorcycle Club Inc
Re: BSA B31, front wheel spindle
« Reply #2 on: 26.08. 2013 23:47 »
G'day Johannes.
That size sounds right. Check the tpi of the tap against the axle thread. It may have been butchered long before you got it.
Cheers
Logged
'51 A7 plunger, '57 A7SS racer now a A10CR,  '83 CB1100F, 88 HD FXST, 2000 CBR929RR ex Honda Australia Superbike .
Australia
Muskys Plunger A7

Offline bsa-bill

  • Wise & Enlightened
  • *
  • Join Date: Mar 2006
  • Posts: 5715
  • Karma: 67
Re: BSA B31, front wheel spindle
« Reply #3 on: 27.08. 2013 10:24 »
yep cycle is 26tpi up to and including 7/16,then goes to 20tpi but 7/16 can be both
Logged
All the best - Bill
1961 Flash - stock, reliable, steady, fantastic for shopping
1959 Rocket Gold Flash - blinged and tarted up  would have seizure if taken to  Tesco

Offline terryk

  • Valued Contributor
  • ****
  • Join Date: Oct 2006
  • Posts: 460
  • Karma: 4
  • Townsville Queensland Australia
Re: BSA B31, front wheel spindle
« Reply #4 on: 27.08. 2013 13:52 »
Heres a helpful thread chart in PDF format so you can download it


http://www.gerardsgarage.com/supportfiles/Threading_Tables.pdf
Logged
1950-53 A10 rigid/plungers, 1958-61 A10 super rockets, 1947-50 A7 longstrokes, 1949 Star twin,
1951-54 A7 plungers, 1940s M21, WDM20s,
1948-50s B33s rigid/plunger/swingarm, 1948-50s b31s rigid/plunger/swingarm
Pages: [1]   Go Up
« previous next »