1946 B31 350cc frame bolts and studs

[brian thombs]

Hi Guys, very simple question, can you tell me are the  studs/bolts that hold the frame sections and plates together BSF  or Cycle thread, I want to replace the nuts but use original my studs.
regards
BT

[idie]

They should be cycle thread.

[martinh10]

The original studs are 3/8" cycle thread (CEI) 26 tpi. 3/8" BSF are 20 tpi.

[brian thombs]

many thanks guys