No doubt about the miles. But what about the time.
I did my last change on November 2006. Only ride 600 miles after that. I don't know if spend on new oil or wait.
Any suggestions?
I usually change the oil/filter once a year. If I log a lot of extra miles in a season, I'll do it twice. I usually wait until spring to do the oil change so it's fresh for the summer, but I've changed it in the fall as well on other bikes and never had a problem with it sitting over the winter.
If you need to do an oil change in the fall, waiting for spring is a bad idea. All the stuff (like unburned fuel mainly) thats bad for the motor sits in there and forms an acid which does an excellent job of etching parts you dont want etched.
I use good old dino and because I think its cheap insurance I will change my oil every 3000 miles or so. When it was new I changed it three times in first 1000 miles. I ride in the desert, its hot and dusty most of the year. For a few extra $ I feel like I'm doing something good.