C15 shock absorber top bolts

[Barnsey]

Could some kind person please point me at some BSA C15 suspension bolts?  The ones which bolt the damper top end to the frame, and also hole the saddle on?
As usual, the previous restorer of my bike used metric ones.  Something he did a lot.  He also had a great love of insulation tape.   

   I'm finding bolts for other BSAs but not the C15. 

   Ohh  yes, I'd better get the nuts too.   I've made that mistake before. 

   BR,

      Ian     

[Greenfield]

Hi Ian
They should be 64-5048 which is 3/8" 26x 1 5/8"
They're at Tradeclassic bikes, ebay etc.

[Barnsey]

OK Thanks,
  I found them listed for Bantams.  I trust that they are the same.  ?  In any case, I have ordered them, so I will find out. 

   BR,

   Ian

[Barnsey]

Bolts have arrived.  The nuts with them are 1/3" wide  whilst the metric ones were 1/4" wide.  Maybe this is why they were fitted.

The problem that I now have is that the luggage rack and the saddle both bolt to the inside of the frame leaving little space for a nut without it rubbing against the smartly painted mud guard.   Now I can remove the luggage rack to get me going but it is a bit of a pity. 

  Maybe I could file down the nut but it would be a bodge.

  SO... If anyone can recommend a good source of 1/4 " wide nuts it would be welcome. Suppliers don't always mention the nut width in the ad. 

   Alternately is there anything else which I need to know? I wouldn't be the first time that the previous owner has assembled something wrongly and I have blindly copied him.

    Regards,

    Ian

   

[Barnsey]

Nah!  No real luck so far. 

  3/8" nuts mostly seem to be 20tpi not 26tpi.  I checked the bolt which I have with my lovely new digital calipers and definitey 26tpi.

    I found a couple of options but both in Germany and the price of shipping massively outways the price of the nuts.   

[JulianS]

These?

https://www.ebay.co.uk/itm/164587238912?itmmeta=01HW07X22S37W9SPA3T0B673TW&hash=item265229f600:g:QvIAAOSwYutayPxN&itmprp=enc%3AAQAJAAAA4K2r8Qw9BwY5Yd0USC3QEoqyAoRFimsjVYZH

Or these?

https://www.ebay.co.uk/itm/291236102545?itmmeta=01HW07X22T00SF7PZ48WTH5CHV&hash=item43cf064191:g:b8UAAOSwDNdV6wa5&itmprp=enc%3AAQAJAAAA4BMq7t7KPrhNrRhpOuawbEjYxKHrS09AlSAVrb%2

[Ian C]

The original nuts (part no. 02-0049) were listed as being 0.218" or roughly 5.5mm thick, so Julians second link to the half nuts should suffice.

[Barnsey]

Good stuff!  Thanks to both of you! I have them on order now. 

[Barnsey]

Arrgh!   The saga continues.

The new nuts arrived but don't fit the bolts.  They start doing up well, but jam after about 4 turns.  I tried three of them but they were all the same. 
SO it looks like the tpi of the nuts and bolts is different although it must be close. 
  Measuring is tricky, even with calipers, but I suspect that the bolt might be 24 TPI rather than 26. 

ADDENDUM:   A few minutes later. 

    Actually I checked on ebay and the bolts which I bought have UNF threads!    SO annoying.  So, could someone now recommend the right bolts to go with the right nuts?   

    Thanks,

     Ian

[Barnsey]

Okay,  I reply to my own thread.

  It seems BSF is 26TPI at 3/8" and UNF is 24TPI at 3/8", so my guess was pretty spot on. 

   What is annoying for the uninitiated is that sellers only give part of the information, e.g. a bolt is sold as UNF but no pitch info and a nut is sold as  26TPI and no thread. Both are then sold as being for BSA.
Anyway, I have now ordered some slim UNF nuts, and we will try again. 

     

[V500]

If you have a mate with a lathe it's a five minute job making full nuts into half nuts, or you could even file them down in the same time if you're handy with a file.
26TPI sounds like BSCy which would probably have been fitted originally.

[Barnsey]

Crazy!  I wanted to replace Metric bolts, which are wrong, with UNF, which is still wrong, Ho Hum!   

  Re the lathe,  I would probably have to find a UNF stud to screw the nut to to go in the lathe jaws, otherwise a good plan.

  Filing too is fine as a final option, but  like to get things absolutely right if I possibly can, but maybe you had figured that out already.

[DAVE BRADY]

Hi,

'Stainlessmiddleton.co.uk' do half/thin nuts in  UNF, BSF and Cycle.  If you do not mind some non-standard bolts then they do a lot of stainless bolts etc.

Dave.

[V500]

  Re the lathe,  I would probably have to find a UNF stud to screw the nut to to go in the lathe jaws, otherwise a good plan.   

Or use a UNF bolt, which is much more common? Do you have an "odd nuts and bolts" box you could look through?

[Barnsey]

I have some UNF nuts now, which fit the bolts 'Hurrah!' 

I think I will be starting a couple more nut tins for BSF and UNF.