Mechanical datasets of a creep rig experiment which quantified grain boundary sliding in an olivine bicrystal sample. A single test was performed for 4 x 104 s at a maximum temperature of 1400 °C. The data from the experiment are presented in a spreadsheet of mechanical data (piston force and linear displacement per time and furnace temperature). A picture of the experimental geometry used and electron backscatter and graphs obtained from the mechanical data are included. The results showed that it is possible to simulate boundary sliding along bicrystal surfaces in a creep rig