After some rides, I realiced the electrical system was outdated ...
So I started the change proposed by jcslocum. Much better the starting, more light during night but while making the chages to the electrical system I had a look at that ugly coils.
Two weeks later I got a set of Dyna coils from Ebay Germany and now

It is much more powerfull in the low rpm range and more smooth.
You all should give a try !
Regards,
Jose Carlos