If you have an iPhone or iPod touch,
Gas Cubby is a highly recommended app. It lets you track fuel use (as well as the mpg on your most recent tank of gas and mpg ever since you started using the app). But it also lets you enter your service intervals, and then it tells you when it's time to do some maintenance.
For example, lets say you change oil every 3,000 miles. You just changed it with the odometer at 8,000 miles. You enter that info into Gas Cubby -- an oil change at 8,000 on the odo. Then, every time you fuel the bike, you enter your fuel use and odometer info into Gas Cubby. Between 15 and 20 refuelings later, when you're coming up on 11,000 miles on the odometer, Gas Cubby will alert you that an oil change is due soon.
You can set service reminders for anything, either by mileage or by passage of time: chain cleaning and lubricating, chain slack check, spark plug check, insurance and registration renewal, valve clearance check, even things like replacing brake hoses, which I believe Kawi wants you to do every two or four years, I forget which. Well, let me check Gas Cubby ... ah, replace brake hoses every 48 months.
You can use Gas Cubby with multiple vehicles. Mine keeps reminding me (and I keep shushing it) to replace the windshield wipers on the Jetta.