Does anyone else find that keeping their bike in good working order is almost as satisfying as riding? I just got my tightest-ever adjustment to my brakes, as good as any LBS has ever done. I barely touch them and they brake; I release them and the tire moves freely. Beautiful.
I'm nowhere near being an LBS-qualitywrench, and the work generally takes a lot longer than it should. But everytime I take something apart that previously was a "black box" to me, and then put it back together, it's almost as satisfying as riding a century.
One thing I love about the mechanics is that there's always something to try, and nothing is as hard as you'd think, even for a klutz like me. For new cyclists, changing a tube is a major accomplishment. Then there's cleaning the drive train, changing a chain, changing a cassette, greasing the seat post, adjusting brakes, replacing brake pads, taking the brakes apart and cleaning them, replacing cables, replacing cable housings, truing wheels, building wheels (possibly my next step), etc., etc., etc.