On the 650 13.5 volts won't do it. My charging system was putting out that much and it would not keep the battery up. Spec on the 650 calls for 14 to 15.5 volts at 5000 rpm. At idle I was getting 13.4 volts and at 5000 rpm I was getting 13.8 volts. Regulator tested marginal so I replaced it with another OEM one. Didn't make any difference. I replaced the stator. Now I'm getting 14.3 volts at idle and 14.9 at 5000 rpm.Charge voltage needs to be 13.5v or more to keep the battery charged. If wiring is okay and voltage isn't there rectifier is the most likely problem. How many miles on your 09?