START ENGINES
With your right or left arm
extended, move your index
finger in a circular motion
 
  STOP
Extend your left arm at
a 45 degree angle with the
palm of your hand facing rearward
  STAGGERED
FORMATION
Extend your left arm upward
at a 45 degree angle with your
index and pinkie finger extended.
This indicate that it is safe to
return to staggered formation
  SPEED UP
Raise your left arm up and down
with your index finger extended
upward. This indicates the
leader wants to speed up
  SLOW DOWN
Extend your left arm at
a 45 degree angle and move
your hand up and down
  SINGLE FILE
Position your left hand over
your helmet with your fingers
extended upward. This indicates
the leader wants the group in a
single file formation. Usually this
is done for safety reasons
  RIGHT TURN
Raise your left arm
horizontal with your
elbow bent 90 degrees
vertically
  LEFT TURN
Raise your left arm
horizontal with your
elbow fully extended
  TIGHTEN UP
Raise your left arm and
repeatedly move up and down
in a pulling motion. This
indicates the leader wants the
group to close ranks
  HAZARD LEFT
Extend your left arm at
a 45 degree angle and
point towards the hazard
  HAZARD RIGHT A
Extend your left arm upward
at a 45 degree angle with your
elbow bent to 90 degrees and
point towards the hazard over
your helmet
  HAZARD RIGHT B
Extend your right leg at a 45 degree downward angle to signal the hazard.
  PISSED OFF
Extend your left arm straight out
with your elbow bent 90 degrees.
Carefully extend your middle finger
to clearly demonstrate your
dissatisfaction with the other guy.
NOTE: It is not recommended
you do this when you are alone

While these are not all the hand signals you will see they are the most commonly used. The