cdi ignition & charging conversion

[MICKREEVES]

Fitted an Electrex world kit to a C15 and it worked for a year or so, then the CDI failed.
CDI replacement got it running again but no charging. & weak spark making starting a big effort.
Stator output is only 6v on each AC wire.

So;
Fitted the old points drive( distributor?) & run direct from the battery. good spark, easy starting again.

Fitted old generator & flywheel, getting 24v ac between the 2 wires, good so far.
But, connecting these ac wires to the modern rectifier with negative earth gets us only a 2v dc output. doh.

does this mean the old stator will not work with a negative earth set up?
i found the old rectifier but not the zenner diode so i cant reinstate positve earth easily.

Does any manufacturer make a conversion that provides 12v charging & a nice fat 12v battery spark?