I have installed a Shindenger SH775 series R/R and am still having problems. I bought a 2000 Vulcan 750, US model in Sept 2015. The bike had a bad stator, suspected bad OEM shunt R/R, bad fan relay in junction box, and a mess of spliced wires in the headlight basket. I couldn't work on it full time, but I have a couple of months effort's in it. I replaced the stator, got another junction box from ebay (full tested IAW Haynes Kawasaki Vulcan 750 manual) and the SH775. Initially I made an adaptor for the regulator to plug into the original wiring harness. The harness needed work so I replace a lot of terminals, connectors and fixed bad splices. The 3 yellow stator wires got real hot so I replaced the 3 bullet connectors with a Walmart 4-pin trailer connector soldered to the yellow wires. This let the yellow stator wire run very cool and easily disconnected for stator testing.
The best I could get from the SH775 was 13.6V at the battery terminals. But the big problem is a 20 mA drain at the battery. I would take a ride, the bike would barely charge and due to the 20 mA drain, wouldn't restart after shutting it down. I wanted to use the original harness because I expected it to work, apparently it has problems. To help isolate the problems and minimize variables, I connected the SH775 as recommend. The 3 yellow stator wires into the SH775 and Red wire from SH775 to positive battery terminal, Black wire to negative battery terminal. Thought I had it fixed. The SH775 with just a little throttle put out a consistent 14.35 V. After a ride, the bike would start right up. But the next day it wouldn't start. The 20 mA drain was still there. I disconnected the SH775, and only applied battery voltage to it, and there was voltage on the 3 stator connectors. Apparently this voltage was causing the headlight relay in the junction box not to release. By disconnection the Reserved Lighting Unit OR the Starter Relay (on side of battery box) the 20 mA drain went away. Further confirming the voltage on the stator wires with bike off, key out is causing the drain.
I did a google search for "SH775 current drain" and found others have same problem. I haven't had a chance to find a work around yet. Some possibilities are relocate the blue headlight wire from pin 8 to pin 7 on the 8-pin junction box connector. Then remove the yellow wire on pin 9 of the 10-pin connector on the junction box. This yellow wire is split off of one of the 3 stator wires to activate the headlight relay after the starter button is depressed. Any other suggests would be appreaciated.
BOTTOM LINE: It appears the SH775 series R/R produces a current drain on a Vulcan 750, but connected correctly it puts out great voltage and runs very cool compared to the OEM shunt R/R.