A group of bicyclists racing.
The bicyclists are racing each other.
Just because a group of bicyclists racing it does not mean they are racing each other.
exists e1 x1 x2 x3.(a_topic(x1) & Actor(e1,x3) & v_race(e1) & (x1 = x3) & of(x1,x2) & n_bicyclist(x2) & n_group(x1))
exists x1.(n_bicyclist(x1) & all x2.(n_other(x2) -> exists e1.(Theme(e1,x2) & Actor(e1,x1) & v_race(e1))))