A tine arm for an agricultural machine for working grass, hay or other crops on the field, wherein one or more tines are mounted on the time arm, the tine arm comprising: - a first arm part and a second arm part which are pivotally connected to each other between a working position and a transport position, and - a locking device configured to lock the first arm part with respect to the second arm part in the working position, wherein the locking device comprises: - a locking pin movably mounted on the first arm part between a locking position and a non-locking or releasing position, and - a first slot and second slot which are mounted on the second arm part, wherein the first slot is arranged to receive the locking pin in the locking position when the first arm part and the second arm part are positioned in the working position to lock the first arm part with respect to the second arm part in the working position, and wherein the second slot is arranged to receive the locking pin in the locking position when the first arm part and the second arm part are positioned in the transport position to lock the first arm part with respect to the second arm part in the transport position - a hinge that hingeably connects the first arm part to the second arm part, wherein the hinge comprises a first hinge part mounted on the first arm part and a second hinge part mounted on the second arm part, wherein the hinge comprises a hinge axis which is arranged at a position spaced from the end of the second arm part, wherein the first slot is mounted on the second arm part at a first side of the hinge axis, and characterised in that the second slot is mounted on the second arm part at a second side of the hinge axis opposite to the first side. - a first arm part and a second arm part which are pivotally connected to each other between a working position and a transport position, and - a locking device configured to lock the first arm part with respect to the second arm part in the working position, - a locking pin movably mounted on the first arm part between a locking position and a non-locking or releasing position, and - a first slot and second slot which are mounted on the second arm part, wherein the first slot is arranged to receive the locking pin in the locking position when the first arm part and the second arm part are positioned in the working position to lock the first arm part with respect to the second arm part in the working position, and wherein the second slot is arranged to receive the locking pin in the locking position when the first arm part and the second arm part are positioned in the transport position to lock the first arm part with respect to the second arm part in the transport position - a hinge that hingeably connects the first arm part to the second arm part, wherein the hinge comprises a first hinge part mounted on the first arm part and a second hinge part mounted on the second arm part, wherein the hinge comprises a hinge axis which is arranged at a position spaced from the end of the second arm part, wherein the first slot is mounted on the second arm part at a first side of the hinge axis, and characterised in that the second slot is mounted on the second arm part at a second side of the hinge axis opposite to the first side.