Thanks for your advice. I went away for the weekend and my wife took the Burgman 650 out for a ride including a stop for gas and about 1/2 hour of ~30 mph traffic riding. She then stopped and shut off the bike to spend some time in a store. When she attempted engine re-start, it cranked slower and slower. Engine cranking slowed to a halt as she didn't get it started. All this is with a new battery.
She waited about 15 minutes for the battery to regain some power and got the engine started on the next attempt. She noted the dashboard clock had reset to 0001 hrs. She then rode the bike for another 1/2 hour and returned it to our garage.
I arrived this evening and did some investigating. The as-found battery voltage was ~12.6v. The engine started. I measured 14.5 volts at battery with the engine at fast idle. I took the bike out for a fast 15-minute ride. No problems observed.
Back at the garage, I accessed the battery, re-started engine and measured battery charging voltage. When the engine is revved, voltage will quickly increase to ~ 14.7 volts then settle back to a steady 14.5 volts.
The battery was removed from bike and and placed on a Deltran Battery Tender Plus. The BT red charging indicator lamp came on then after a few minutes the charger displayed alternating red and green LEDs; indicative of nearly full charged. That was ~1/2 hour ago. (please see add'l comment below)
Originally Posted by QuantumRift
So is the trunk light turned off when the seat is closed - I think that's the purpose of the question.
Disconnect the POS batter terminal. Connect a 12V test light between the red cable and the (+) battery terminal. If it now glows bright, you have a very heavy battery drain. One by one, pull the fuses (mark what goes where), both at the fuse panel and under the seat.
It's just possible that the alternator just won't keep the battery charged, if you find that by boosting the battery with a charger keeps it going. What kind of charging voltage are you seeing?
Originally Posted by Ray Nielsen
Any possibility that any other accessory circuits are connected? Are there more than one wire on the positive battery termnal? That would indicate another circuit.
It appears the only wires connected to the battery positive terminal are from the stock wiring harness. There are no dealer-installed or owner-installed electrical accessories on this bike.
The Battery Tender now indicates solid greed LED after ~35 minutes of charging. The condition whereby Battery Tender is not able to display battery-full-charged (solid green LED) if
battery installed in bike is suspected to be related to the low problem... Any thoughts on this?
I'm starting to suspect an intermittent problem in the voltage rectifier. Is it possible the former owner damaged diode(s) by charging the battery while installed in the bike? Have you come across any operating experience with a diode failing when hot; only to resume functioning normal when it cools down?