LCGB Forums

I would like to fit an original Ducati rectifier casing but modified internally as below. Does anybody have any experience of using these? Presume this will replace the popular electronic regulator but not sure if I would need a CDI or could I use a standard looking 12v coil. Any thoughts?


http://lambrettapals.freeforums.org/dow ... 2b62b4a6ac
http://lambrettapals.freeforums.org/dow ... 2b62b4a6ac

Yes I've used them and converted them as well.

If you do your own it's best to fit a small heat sink behind the rectifier and zenor even though they are sat in the old rectifier box heat will transfer through to an alloy heat sink and loose heat to the surrounding air, loosing as much heat as possible will prevent the soldered connections Becoming undone with heat.

It's best to use the correct crimp connector on the Zener connection as soldered connections here often un-solder with heat.

Coil or CDI will depend on the stator you use points or electronic.

I use something similar,
solid state rectifier hidden in the original Ducati black box,
I use an external heatsink that has a 12V negative earth zenor diode at the back.
I use it on a 12V DC points system done from a world famous Lambretta electrics artist ,
I can also use it with the recent DC mod for modern 4 pole stators,
(full guide provided from the same world famous Lambretta electrics artist )
information can be found here
viewtopic.php?f=7&t=4551

On my TV I carved everything out of it & fitted a BGM regulator to retain its standard looks

You can also use the Varitronic reg or one off a moped as the same size.

Thanks for all your replies guys.

I did one like the above a few years ago but opted for the Wassel in the end. I'm waiting for a mate who has a 6v BGM one on the way. The unit should fit inside and it's a modern version of the Zena all potted in and sealed ready for use. I didn't realise they did a 6v version till another guy with a Luna was wondering why he was only getting 6volts on a 12 v conversion. The 6v one is a few quid cheaper and looks identical. He had ordered the wrong one. Mr B swapped it and he now has great lights. Of course this will give AC lights with a DC trickle charge for lights

This is the Casatronic,
I also used a Ducati cover for the ultimate disguise











The solid state rectifier in the original Ducati box,sorry for the bad quality pictures,I had a crappy camera then,
I still use the original type od fuse with this one.

Thanks Guys, this is certainly an informative forum.

I have a question for Dimitrios, you show a picture of the potted regulator inside a Ducati cover. When covered, does it not prevent cooling of the regulator possibly leading to overheating? I suppose the wattage your mag pushes out and the lights you use will dictate the amount of heating.

No heating issues with the potted regulator,it is a modern unit,it only works with the DC stators.
http://www.rexs-speedshop.com/epages/es ... oducts/BR1

You'll get heating issues, if you try to hide a zener diode inside the Ducati box.
I have mine on the rear mudguard,fitted on an old motorcycle heatsink.



The base is a homemade product



I've done a small batch for forthcoming projects.







They only need some polishing...

I bought a modified Ducati regulator with Zener diode and bridge rectifier many years ago and when I try to use and connect the red (rosso) terminal to the battery it shorts out blowing the fuse so I must be doing something wrong. I was trying to enclose a photo here but is too large to send. Not sure how to reduce the size.

I use this site to upload pics

http://tinypic.com/

The connections in my box.

Managed to upload and obtain this link below to show my existing Ducati modified with the bridge and zener diode. You can see that the battery red connection on the left hand side is connected via the fuse to the purple connection and then on to the zener diode and one of the 4 bridges. When I connect the battery to the red terminal the fuse melts.
Does anybody have a wiring diagram for this arrangement so I can check it please?
http://imgur.com/a/vK2eC

salient wrote:Managed to upload and obtain this link below to show my existing Ducati modified with the bridge and zener diode. You can see that the battery red connection on the left hand side is connected via the fuse to the purple connection and then on to the zener diode and one of the 4 bridges. When I connect the battery to the red terminal the fuse melts.
Does anybody have a wiring diagram for this arrangement so I can check it please?
http://imgur.com/a/vK2eC

Multimeter your earth to zener live I think your zener might be the wrong polarity.

You have the positive on the rectifier earthed (looking at your photo) if it's wired into a negative earth Zenor it will short out and that will blow the fuse.

If it's wrong just change the connections on the rectifier so that the negative is the earth, and make sure your battery is connected the correct way around to suit the Zener and the way you wire up the rectifier.

I can't help with a wiring diagram as most of the wiring/electrical conversions I do is purely from memory.

Thanks for your response. Not sure how to change the connections as the zener is bolted to the earth. Presume will have to unsolder the terminal before testing?

Can you take some more pictures from different angles?

Thanks Dimitrios. moire pics enclosed
http://imgur.com/a/MVZbM

All solid state rectifiers have this diagram.



In this pic,there are more fitting instructions.



This system is correctly wired,it has a negative earth zener and it is wired as a negative earth system.
If the battery has the negalive pole earthed,everything will work fine.



He uses this negative earth zener.



In your case,
you also have a negative earth wiring,
if your battery's negative pole is earthed then you only need a negative earth zener,
now, here is the question,IS your zener negative earth?
Your zener code is bzy91c15,
if it is negative it might need replacing,if it is positive you must change it to a negative,
in the second case you can also change the wiring to positive earth (you keep the zener) plus use the positive battery pole for earth,
personally,I'm not fan of positive earth.

Looking at the symbol on my zener, the cathode appears to be the threaded stud which is connected to earth. Thus I understand that current can flow from the soldered anode terminal through the zener to the cathode earth. Problem is that because there is no resistance in the circuit, the current flow can be high thus blowing the fuse. Is this how such a bridge circuit should work? All the circuits I see seem to have a resistance to control the current flow.

salient wrote:Managed to upload and obtain this link below to show my existing Ducati modified with the bridge and zener diode. You can see that the battery red connection on the left hand side is connected via the fuse to the purple connection and then on to the zener diode and one of the 4 bridges. When I connect the battery to the red terminal the fuse melts.
Does anybody have a wiring diagram for this arrangement so I can check it please?
http://imgur.com/a/vK2eC

My reply referred only to the phot of this rectifier, whic I thought you were referring to.

Sorry for any confusion