disclosure of steps 54 through 56 and only disclose the first absorbing force control sub routine 53 fig6 b represents a flow chart of the first absorbing force control sub routine 53 in step 60 the beginning of an execution of the program is defined in step 61 the newest detected shock force dg1 new is transferred to the old detected shock force dg1 old in step 62 the detected signal at the shock sensor 30a is transferred to micro computer 41 via low pass filter 42a analogue digital modulator 43a and input interface 41e and deemed as the newest detected shock force value dg1 new the former detected shock force value dg1 old represents a former shock value to the vehicle body bd the program detects during its execution ranging from step 63 through step 67 whether the shock force which has been detected by the shock sensor 30a is in the rising condition or descending condition and calculates by using the resulting condition an extreme value dg1 max maximum value and minimum value of the detected shock force in detail in step 63 it is determined whether the flag udf1 is in 34 1 34 or not 34 1 34 represents a.