BSA Parts List 1973, B50MX

BSA Parts Catalogue for 1973 B50MX Victor 500 Moto-Cross

Re-printed coil bound copy of the factory publication, A4 page size.

Covering Frame and Engine Numbers (at start of production year)

In 1969 a new numbering system was introduced using a two letter prefix for the month and model season year. 

The first letter designates months as follows:
A: January  B: February  C: March  D: April  E: May  G: June  H: July
J: August  K: September  N: October  P: November  X:  December

The second letter is the year code:

H: Aug 1972 to July 1973 for bikes made for 1973 selling season.

Numbering started at 00101 and carried across all models.