CDI for LML engine...need your help!

Hi geek vespa Community,

Recently installed brand new LML 5 ports engine on my 67 VBC....

Everything runs.....but I blew up 2 CDI units* (in very few Kms) so I do not know where to go now.
I red in 'S.I.P.' site that the LML engine produce a bigger electric output than a let say, original vespa engine.(Piaggio cdi coil need 480 ohms when LML ones 390 said to be lower resistance.)

Q: What type of CDI /coil unit should I need? 

Thanks in advance..I hope that some day, it will be running like it should be.


* ducati type refer to:

I don't know who told you such disinformation, but the LML ignition plate does not produce a bigger output regarding the ignition circuit (as there are 2 circuits on the plate).

The fact that you've blown up 2 CDIs depends IMHO on the poor product quality (and manufacturer).
It really can be possible that this happens.

Please don't give too much attention to electrical resistance.
Piaggio says in its original manual: 500 Ohms +/- 20 Ohms.
But as SIP told me, Piaggio overceeds their own tolerances according to their supplier (as they don't produce the stuff themselves).

So the only thing for you is to make a quality claim to SIP and let them send you a CDI which is working. Also you could consider to try another ignition plate (it could also cause the CDI to blow)

As beformentioned, it seems pretty much "only" a quality issue. As far as I see, the ignitiion plates with "original Piaggio" plastic bag and those on the LML engine come from the same manucaturer in India.


Hello Marc,

YES: instead of the original LM type ignition (CDI box + ignition coil), you can also use the DUACTI type.
You will need to modify the ignition plates' wiring and you will also need a mounting bracket (as the LML type stuff doesn't fit with the DUCATI CDI).

Works perfect, just fitted a VBA with this type of engine.