An axle assembly (310) has a longitudinal axis and first and second ends, the axle assembly configured for rotatably mounting a wheel and hub assembly on an axle portion or the axle assembly, the axle portion located between the first and second ends, the axle assembly configured for affixing to first and second structural members (301, 302), at least one of the structural members (302) comprising a substantially closed bore orifice (306) wheel mounting point or dropout, said dropout having a first side configured for the axle portion to extend therefrom when said axle assembly (310) is fixed to said point and a second side, the axle assembly (310) comprising a first fixing means (309) at the first end for releasably fixing the axle assembly (310) to the first structural member (302) and a second fixing means (311) at the second end fog releasably fixing the axle assembly (310) to the second structural member (301).