Lancia Motor Club

Does anyone have a diagram to show how to connect the Aprilia's dynamo to a Bosch voltage regulator (or similar) please??

I don't know, if your Aprilia is 6 or 12 Volt, but the connections are the same. I happen to have a spare 6 Volt Marelli dynamo for my Augusta connected for reverse running. Attached picture 4210 show connections. The white cable is the "+" from the insulated brush holder, the black cable is from the neg. end of the field coils. Disregard the lock nuts and the print in the picture as the regulator is an electronic one, but the base is original.

If your regulator is in working order, fine. If not, I recommend to install an electronic regulator. Like the DVR4N, 6-16A or  DVR4N 12-8A This brand fits into the original housing. But it can be installed remote. It will deliver power already at much lower RPM and will limit the voltage to a value which prevents boiling of the battery.

https://www.dynamoregulator.com/

I hope that helps.

Karl

Evening Karl,

many thanks for the info and link, that's really helpful.  After some internet research and testing today, i have realised that the dynamo is just not providing any significant output (about 1.5v max!)...so i now need to get my dynamo fixed/rebuilt...anybody have any suggestions of good companies for doing that?  (I have already flashed it to make sure it is properly polarised...and that did not give any improvement).

For your dynamo , I have heard good things about Morgan & Sons 0 44 1306 881544 in Dorking UK   

I took my tailgate opening motor on my S1 sport, which is quite complicated electrically, to Robson and Francis in Mitcham South London. They did a complete rebuild for about £120 which I though quite reasonable. They said they could fix anything electrical. Maybe worth a call 0207 733 2353. If you take it there do not be put off by the state of their workshop, looks "busy"

many thanks for the suggestions...Dorking is closest to me, so will try there in the first instance...

Very interesting, I like your solution, Karl. Although I have a few regulators, the insulation has become brittle due to age and doubt if any of them work. 

I have had both my Lambda magdynos converted to electronic regulation. I could not face the festering 1920s internals. The new regulator fits inside the existing space in the unit, and has provided a carefree solution.
It takes a bit of an attitude change, as the new scenario looks at battery voltage and its requirements, rather than "balancing the discharge", so there's rarely much variation shown on the ammeter, except a short boost after using the starter motor. For total logic one should probably fit a voltage meter rather than an ammeter, but that was a step too far for me.
My auto electrician friends (I am not an electrical expert) tell me that  modern batteries, designed for alternator systems,  have the ability to burn out a dynamo by consistently requesting maximum charge. Electronic conversion changes the demand to what is actually needed at any one time, if you have a large capacity battery that will mean a less demanding life for the dynamo.

I received my dynamo (with a new solid state regulator attached and wired up) back from Morgan and Sons (in Dorking) last week.  So far it is working very well and the battery is now being charged.  I would recommend them, not cheap, but not too expensive either.