  Graphene nanoribbons provide an opportunity to integrate phase-coherent
transport phenomena with nanoelectromechanical systems (NEMS). Due to the
strain induced by a deflection in a graphene nanoribbon resonator, coherent
electron transport and mechanical deformations couple. As the electrons in
graphene have a Fermi wavelength \lambda ~ a_0 = 1.4 {\AA}, this coupling can
be used for sensitive displacement detection in both armchair and zigzag
graphene nanoribbon NEMS. Here it is shown that for ordered as well as
disordered ribbon systems of length L, a strain \epsilon ~ (w/L)^2 due to a
deflection w leads to a relative change in conductance \delta G/G ~ (w^2/a_0L).
