I have an 04 R1150RT and have been having starting issues which I had been attributing to a weak battery and cold temps.
It is now to the point where it won't rotate the engine at all.
I have tested the 2 year old battery for voltage and load testing which it has passed both tests. When trying to start the engine the voltage across the terminals drops from around 13 to around 5.
I removed the starter tested it on the floor using the battery in the bike. It seems slow and weak to me but I have nothing to compare it to. I also hooked it up to the battery in my truck and got identical results. So, I don't feel the battery is the issue.
I realize this also leaves the starter relay, but I wanted to rule out the starter before I replace the relay. All connections look good and corrosion free.

Here is the link to the video I made of testing the starter on the floor.
http://www.youtube.com/watch?v=hM4hMQF0jro