A spring for a caliper body wherein said spring is shaped to be arranged straddling a brake disc for applying an elastic action on at least one brake pad to bias it away from said brake disc; wherein - said brake disc is adapted to rotate about a rotation axis (X-X), which defines an axial direction (A-A), parallel to said rotation axis (X-X), a radial direction (R-R), orthogonal to said rotation axis (X-X), and a tangential direction (T-T) orthogonal both to said axial direction (A-A) and to said radial direction (R-R); - said at least one brake pad comprises a support plate, which supports friction material, said support plate comprising a plate edge forming at least one first plate thrust portion and at least one second plate thrust portion; - said caliper body comprising a first elongated element or wheel side elongated element, a second elongated element or opposite wheel side elongated element, a first side bridge and a second side bridge adapted to connect said first elongated element to said second elongated element straddling said brake disc and leaving a central portion of said caliper body free from a central connection bridge, - said spring comprises a spring body; said spring comprising: - a first thrust portion adapted to apply said elastic action on said first plate thrust portion of said at least one brake pad, biasing said brake pad at least away from said brake disc in an axial direction (A-A) and in a radial direction (R-R); - a second thrust portion adapted to apply said elastic action on said second plate thrust portion of said at least one brake pad, biasing said brake pad at least away from said brake disc in an axial direction (A-A) and in a radial direction (R-R); - a first coupling portion adapted to couple said spring with said first side bridge; - a second coupling portion adapted to couple said spring with said second side bridge on a tangentially opposite side with respect to said first coupling portion, - a backing portion adapted to abut against a caliper pin planted in said caliper body or a caliper tie-rod screwed to said caliper body avoiding coupling with said caliper pin or said caliper tie-rod, characterised in that said spring comprises at least one concave spring portion having a concavity facing towards said brake disc so that at least said backing portion is elastically movable in a radial direction (R-R) towards said brake disc between a rest configuration and at least a work configuration, elastically stressing said first coupling portion and said second coupling portion along said tangential direction (T-T) in opposite directions, in which, in said work configuration, said backing portion abuts against said caliper pin or said caliper tie-rod, stressing said first coupling portion and said coupling portion against said first side bridge and against said second side bridge, respectively. - said brake disc is adapted to rotate about a rotation axis (X-X), which defines an axial direction (A-A), parallel to said rotation axis (X-X), a radial direction (R-R), orthogonal to said rotation axis (X-X), and a tangential direction (T-T) orthogonal both to said axial direction (A-A) and to said radial direction (R-R); - said at least one brake pad comprises a support plate, which supports friction material, said support plate comprising a plate edge forming at least one first plate thrust portion and at least one second plate thrust portion; - said caliper body comprising a first elongated element or wheel side elongated element, a second elongated element or opposite wheel side elongated element, a first side bridge and a second side bridge adapted to connect said first elongated element to said second elongated element straddling said brake disc and leaving a central portion of said caliper body free from a central connection bridge, - said spring comprises a spring body; - a first thrust portion adapted to apply said elastic action on said first plate thrust portion of said at least one brake pad, biasing said brake pad at least away from said brake disc in an axial direction (A-A) and in a radial direction (R-R); - a second thrust portion adapted to apply said elastic action on said second plate thrust portion of said at least one brake pad, biasing said brake pad at least away from said brake disc in an axial direction (A-A) and in a radial direction (R-R); - a first coupling portion adapted to couple said spring with said first side bridge; - a second coupling portion adapted to couple said spring with said second side bridge on a tangentially opposite side with respect to said first coupling portion, - a backing portion adapted to abut against a caliper pin planted in said caliper body or a caliper tie-rod screwed to said caliper body avoiding coupling with said caliper pin or said caliper tie-rod,