Join Date: Jul 2007
Location: Anaheim, CA, USA
The original "Powerlet" socket on the left side of your 2006 K1200GT is connected to the Canbus. The Canbus is computerized - it can shut off any circuit on the motorcycle if it detects excessive current, for example. That's why your K1200GT does not come with fuses or circuit breakers.
Because it is connected to the Canbus, the side socket is special. The Canbus limits it to 5 amps of current. If you plug an electric jacket liner and draw too much current, the Canbus will shut it off. The Canbus also shuts off the Powerlet outlet on the left side about a minute after you turn off the K1200GT with the key. It is the "protective" behavior of the Canbus that blocks charging from normal chargers. If you want to use an ordinary charger, you must connect it directly to the battery See suggestion #2, below.
There are ways to work around the issue:
1. SMART BATTERY CHARGER THAT WORKS THROUGH THE POWERLET OUTLET
There are smart chargers from BMW and others that have been specially programmed to recognize the Canbus-protected outlet. They perform special "handshake" communications with the Powerlet outlet to charge the K1200GT.
* I have an Techmate-brand Optimate 4, which I highly recommend. It is designed to work through the Powerlet outlet and it works great. You can buy it online from many sources, such as Amazon.
* BMW Charger - Search for part 77028551897, 77027722471; or older: 71607688865; 72607679040
2. USE THE KNOCKOUT TO INSTALL A SECOND POWERLET OUTLET, CONNECTED DIRECTLY TO THE BATTERY
As you suggested, install your own Powerlet outlet in the knock-out, and connect it directly to the battery. Many people have done this, and doesn't hurt to have a direct-to-battery Powerlet connection anyway. You can buy installation kits that come with with the covered outlet, the correct wires, etc. It is an easy project.