BSA Owners' Club Workshop Discussions

The BSA Workshop => Singles => Topic started by: Barnsey on 09 Feb, 2025, 10:46

Title: Tail light for C15
Post by: Barnsey on 09 Feb, 2025, 10:46
The top two bolts holding the tail light nacelle onto my C15 have gone missing.  Does any one know what size they should be? They look to be larger than the two lower ones.

 Also, a recommendation of rubber edging strip to stop the nacelle wearing through the paint on the mudguard would be welcome.

 
Title: Re: Tail light for C15
Post by: Barnsey on 09 Feb, 2025, 14:56
I found some rubber trim on EBay, £5 for 10m, Bargain!
Title: Re: Tail light for C15
Post by: Barnsey on 09 Feb, 2025, 16:11
I measured the bolt holes.   IF the lower ones are 1/4"  then the upper ones must be closer to 1/3"
Title: Re: Tail light for C15
Post by: V500 on 09 Feb, 2025, 17:28
 Don't do thirds...1/4" next step 5/16ths.
Title: Re: Tail light for C15
Post by: Barnsey on 09 Feb, 2025, 17:56
Yep. I realised my mistake.I ordered some 5/16" screws via ebay. It seemed a dumb question, but my bike uses a right mix of screw threads, BSF, UNF, Metric etc. 
Title: Re: Tail light for C15
Post by: Tigerfeet on 09 Feb, 2025, 18:12
My understanding is the the C15s all used cycle thread for everything. The other threads started to get mixed in around 1967? So anything on your bike that isn't cycle thread has been added by previous owners....  (Mine was a similar hothchpotch - but I got so fed up searching through different spanner sets each time I needed to undo a nut, I replaced all the wrong stuff.)
Title: Re: Tail light for C15
Post by: Barnsey on 09 Feb, 2025, 18:48
Agreed.  I just bought a saddle which had metric screws on the mounting bracket.