This only applies to the 6 volt dynamo fitted to Ural M63/M66, Dnepr MT9 and the sidevalves
At F2 Motorcycles we get emails about the L414 dynamo not working on bikes that have not been used for a while. 99% of the time there is no need to replace it.
I thought I should share my standard reply to these emails.
It goes something like this.