Ninja 250 Rider's bookshelf

Riding Technique

Proficient Motorcycling and More Proficient Motorcycling by David L. Hough

A Twist of the Wrist II by Keith Code (This one is for street riding. The original TOTW was for racers.)

Total Control: High-Performance Street Riding Techniques by Lee Parks

How to Ride a Motorcycle by Pat Hahn

Sport Riding Techniques by Nick Ienatsch

Maintenance and Repair

Official 1986-2005 Kawasaki EX250 Ninja Factory Service Manual

Official 1988-2006 Kawasaki EX250 Ninja Factory Service Manual Supplement

Motorcycles: Fundamentals, Service, Repair by Bruce A. Johns, David D. Edmundson, Robert Scharff

Other

Zen and the Art of Motorcycle Maintenance: An Inquiry into Values by Robert M. Pirsig

Ghost Rider: Travels on the Healing Road by Neil Peart

Perfect Vehicle: What It Is about Motorcycles by Melissa Holbrook Pierson

Long Way Round: Chasing Shadows Across the World by Ewan McGregor, Charley Boorman