Originally Posted by JimVonBaden
My bike must be special then. I have never used a tender on any bike, including my 05 R1200GS, and have left it sit for weeks, while I was out of town on travel, and never had it not start, even in sub-freezing temps. The bike is always parked outside.
While I agree the battery is marginal, I disagree you MUST use a tender on them. That is, unless you leave it parked for months.
Measure the current draw with the ignition off. I would be curious to see what you get. Why speculate? It is an easy measurement to make. Maybe I have two bikes with CPU problems - seems unlikely, but it is possible.
I would speculate that the "typical" later model GS's or HP2's would have about three weeks to a drained battery incapable of starting the motorcycle. To avoid this situation you MUST use a tender.
Please make the measurement, I am very very curious why your bike seems to be so special.