So sorry,
Honda CB550F 1977.
If I read everything in the link I've posted previously this seems 200% my problem. And frankly can't think of anything else anymore.
As told, no wires are touching somewhere, all carefully checked.
I measured the 1st rectifier and it was broken (putting black of multimeter on the red on & red of the multimeter on every yellow one, you need to read 0.5 to 0.6 ohms).
New one that I measured, all good!
Started, main fuse blew, rectifier really hot, measured and broken as well.
Now just would like to know how to measure my ohms on the alternator widings etc & how to get it off the bike...
Thanks in advance!
Brgds,
Wannes