I'm thinking of spending my winter months learning about bicycle mechanics at the same time giving back a little at our local Free Ride program.
I can already do the basics, repair a flat, change brake pads, adjust brakes, change a chain and replace rear cassette.
What should I concentrate on first, to add to my skills?
I was thinking learning how to properly adjust derailers and learning how to true a wheel might be the most useful in basic bicycle maintenance and also emergency repairs while on tour.
Anything else I should have at the top of my list that will be most useful?