Bearing, eng mainshaft, double ball, self centre, Norton singles

Bearing, mainshaft, for Norton single cylinder engines (ea). This bearing is double row balls, self centering. Early engines have two bearings, later engines (post 1934?) have three bearings (2 x double + 1x single). All military Nortons had two of these double row ball bearings + the single row bearing, Civilian machines post 1934-5 had a ball bearing and a roller on the drive side and one roller bearing on the timing side. This is a much cheaper alternative to the roller bearing and just as effective.
Original Part Number:
9033; A2/30; 17704 - Mainshaft ball bearing driving side x1
8858; A2/32; 17702 - Mainshaft roller bearings x2