Diode on dynamo output wire

[12jslater]

I was told it was possible to fit a dynamo on the output wire with a diode as to stop and voltage flowing back into it and potentially damaging it, this seems more important with the quality of modern voltage regulators, I was wondering how and what type of diode to fit?

Thanks !

[geoberni]

I've been told a lot of things over the years, some true, some not, some partly true, a bit like Chinese whispers.....

I believe Vintage cars and bikes, those using magnetos, often had very rudimentary cut out systems, or possibly even manual intervention by the driver/rider to control their charging system. This might be what you are thinking of.

It's an interesting question though.
What failure of a Voltage Regulator would cause the battery to stay connected to the dynamo on switch off and would it damage the dynamo, or just flatten the battery.