I know things... A lot of things.
Join Date: Feb 2015
Motorcycle: GSXR 750 K4
Re: Charging issue
I haven't followed the conversation very closely, but note that if the stator and rectifier test ok, but there's still no charging, the issue is likely to be in the wiring between them (as I think Kartel already mentioned). Bypassing the OEM wiring entirely should not be necessary though and could introduced more complications and potential dangers if not done right. Check the wiring and couplers between the stator, rectifier and the rest of the bike, and check for signs of overheating, loose, dirty or otherwise improper connections. Fix as necessary.
The weak starting problem is probably unrelated to this, but is also likely to be due to bad wiring, although other causes are possible (a bad starter relay, bad starter, etc)