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BICYCLE CLASSES
frame, wheel by ISO 5775 and handlebar — three signs of a class, and what the frame is rated for
Free
CAR CLASSES
segments A to F by length and bodies by box count — how to name any car you see
Free
MOTORCYCLE CLASSES
rake, trail, wheelbase and seat height — six classes drawn at one scale
Free
THE RACING LINE
one corner, three apexes, the time computed
Free