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
TYRE SIZE
what the sidewall marking is made of and what it works out to
Free