Since I have owned the Moto Guzzi California II the last couple of years I have had issues with the charging. I would go on a journey and the charge guage would read no volts. I knew some thing was not quite right. It also meant that I would have to bump start the Guzzi or get a jump start.
So I carried on working on the issue.
It does not help that I had the frame powder coated which made it hard to conduct electricity through the frame. When I was rebuilding it from parts, I could see that the earth worked through my body when picking up the wires. I also could not buy new bulb holders for the dash and only cleaned them.
If you have any charging issues with your bike have a look at my previous posts for help.
My issue could have been the Alternator rotor bosch type or the voltage regulator. With the help of Baldrick I managed to find that the rotor was slightly out of specification. In the pictures you can see the two sets of figures. As it was out of specification talking to Baldrick we decided to renew. I was trying for second hand parts but none were available so went with new.
It is hard for me as the bulb did not come on all the time so this could have been the issue. I have left the new parts on and for the past few weeks since October the third, every day it has worked. When I turn the ignition on, the red charge light is on, then when starting as the bike revs, the red light goes out and the charging indicator sweeps into the green area. So from this fix a new rotor and voltage regulator was fitted.
I downloaded the documents from Gutsibits who have a download sheet to help with diagnosing electrical problems and what could be the cause. I worked through this and Part of the job of the bulb is to energise the rotor and the fact that I had a intermittent connection on the bulb might have made the diagnosis harder to find.
I hope your bike is a lot easier to fix. Keep working and searching the net for help. If you are local to London then Baldrick is a very good mechanic and a character. Give him a call. Check his website out at http://baldricksworkshop.co.uk/