I thought I'd share my experiences on doing my first oil change on the GTS. Hopefully greasy or someone knowledgeable will jump in if I've made any errors. Jess, if you feel this belongs in the tech library feel free to move it.
Basically, here's the drill:
First off, you need to support the bike in some other way than the centerstand. I had a couple of screw eyes already set into a beam from a prior project, so I used some tiedowns and a canyon dancer harness to support the bike. A wheel chock would surely be simpler, but this is what I had.
For tools, I had an oil filter wrench (the old one was on WAY tight), a 'breaker bar' and a torque wrench. You'll also need a 24mm socket, and if you don't remove the exhaust you might need an extension. (It is a little tight in there.)
The first step was loosening the oil filter with the bike cold. This way you can get some grip without worrying about burning yourself on the exhaust. You're not taking it off, just getting it so you can easily remove it when the bike's hot. I did the same thing with the drain plug.
Then I put the drain pan underneath and ran the GTS for a few minutes to warm it up. This makes the oil flow out more easily.
Shut off the bike, unscrew the dipstick and then unscrew the drain plug. You may want to use gloves to prevent burns from the exhaust or contact with hot oil. Pull out the oil screen and check for metal shavings (bad) or other gunk in there. It should be clean.
Once most of the oil has drained out the drainplug, unscrew the oil filter and get the remaining oil out. Once the oil has drained out, smear a bit of oil on the rubber gasket of the new oil filter and screw the new filter back on. Hand-tight is fine (spec is 4-6 Nm or Newton-meters, which is not all that tight).
Replace the oil screen and screw the oil drain plug back on. Torque to 24-30 Nm.
Now slowly fill the bike with new oil - don't overfill. Run it for a couple of minutes and check for leaks. Let the bike cool 10 min. and recheck the oil level; adjust if necessary.
And that's pretty much it.