It disturbs me greatly when I see someone riding a bike, which they obviously spent a fair amount of money on, and it hasn't been properly maintained. For one, if you have the money to buy such a bike, you probably have money to take it in once or twice a year. If not and you forked out everything you had on the bike, then by god, do it yourself! Don't let such a beautiful machine go to $#*@!
For those who have a little less of a bike and think that it's not worth anything so it doesn't matter.....shame! Less expensive bikes need to be taken care of even more than the higher quality ones. If you don't maintain them, they won't last long and you won't be riding.
The bare minimum maintenance can do wonders. If you do at least the following three things it will allow you to keep riding longer and cut down any expensive repairs or replacement parts down the road.
DON'T LEAVE IT OUTSIDE! The weather isn't good for it, especially repeatedly. And you leave it more at risk to be stolen.
IF YOU RIDE IT ON DUSTY ROADS, MUDDY TRAILS, OR WET DAYS, THEN WASH IT! Spray it of and wipe it dry, making sure to wipe all components and the chain.
LUBRICATE IT! After you clean and dry it make sure to lube all moving mechanisms lightly with bike lube! Make sure to get every link in the chain. Wipe of any excess.
*Note: It is still recommended to take it in to a qualified bike tech once or twice a year for a tune-up.