I just found this on a V-Max WebSight:
I have not checked my bike yet ( 89 ) to see if this minor fix applies to Ventures, as well as the V-Max.
Its the Red wire from output of the Voltage Regulator going to the Main Fuse holder then to the Battery Positive Terminal.
The Information claims this connecting point is just " Crimped" and should be Soldered. Why, because there is a 1 volt voltage drop across the crimp connection. At least thats what is Claimed. I can't confirm it yet.
Check this web address, http://www.vmaxoutlaw.com/main.html
On left of page click on v max tech + Info:
Then Scroll down to and find, " Crimp" connection fix.
It gives Schematic information, and some good photographs as to
how to do the " fix " The Fuse holder looks same as on 1st Gens.
I will check mine tomorrow, or as time presents itself, being that I am now Retired, Time is in fairly short Supply. And its January and its Cold in the Garage, and I just got home with a 6 pack !!