I had a problem with my voltage regulator a while back. it degraded to little over 4 volts, dimming the system way down.
While your cleaning your grounds, disconnect the voltage regulator and start the sled. If the lights are brighter then you have found your problem!
NOTE: don't rev it too much (over 2300 rpm). You could over voltage the system and it could blow all of your lights.
My Current Sled:
1997 Yamaha Vmax XTC 600 Twin ER 6290 MI - Stock... for now...
1979 Yamaha Exciter 440 6042 MI (9825 KM)
1979 Yamaha Exciter 440 7,000 MI (11266 KM)
WAKE-UP AND SMELL THE TWO STROKE
2012-2013 Miles: 1739