A system for supporting a cutterbar of a crop harvesting header includes a first arm pivotably secured to the header. The first arm includes a first portion configured to support the cutterbar. The first arm includes a second portion including a torsion device having a mass of elastic material connected to an adjustment assembly. The second portion is configured to be pivotably rotatable about an axis by the adjustment assembly to selectably increase or decrease a force appliable to the first portion in order to raise or lower the first portion with respect to the header. A load limiting apparatus limits an amount of torsional force that is applied to the mass of elastic material by pivotable rotation of the second portion about the axis.
