1. With the Throttle trigger (K) in idle position, the Latch (A) is
pushed, the head (B) of Latch comes off Throttle stopper (C).
Throttle stopper (C) is pushed to the neck (M) of Latch by Stopper
spring (D).
Then projection part (E) of Throttle stopper disengages from dent (F)
of Handle fixture.
In this state, the Rear handle can be rotated.