Early alternator models

Hello Steve - Never seen one with an adapter and I've seen a lot ! Also not seen a factory produced alternator crankshaft in a pair of dynamo cases either. Of course people did that themselves with a blank over the timing-side opening and a reworked drive-side for the alternator mounting. The inner primary chain-case would probably need some modification - but it was done. Are you thinking about a new project or thinking out loud ? Cheers, Howard

Hello again Steve - Are the crankcases a matched pair ? You can usually see a stamped number inside each half. On the drive-side it is usually on a flat part around or above the main bearing recess. On the timing side it is sometimes in the timing chest. The number is usually quite faint and often inside an ellipse. There can be an accompanying letter - e.g. Z606 ; F67 ; 194 ; 50 . When leaving the factory in Birmingham the numbers always matched. These combinations are from some of my cases. Good luck with the project. Regards, Howard

Somewhere in the NOC records there is a mention of a good number of Dynamo 99s being exported to various countries after 1958. Around 200, I understand, with the French Police taking a large proportion.

Dynamo crankshafts were a favourite of the Club racers who would have the primary drive end drilled out and a flapper breather fitted. leaving the original breather shoulder free to be tapped for an oil feed to the camshaft. A recommended Dunstall mod I believe.

In the 70s I also came across an engineering / machining business based in Hampshire, who would drill and thread the end of the crankshaft to take a large shouldered bolt. On which, an alternator rotor could be placed. I don't believe that this mod caught on. I am informed that modern welding techniques will now permit the addition of chunks of metal to construct an extension of the shaft.