A cover fabric for a power transmission belt, the fabric woven from warp yarns and weft yarns; the warp yarns and weft yarns each plied from a first filament yarn and a second filament yarn; the first filament yarn comprising higher tensile strength fibers than the second filament yarn; and the fabric woven in a modified twill pattern. A toothed belt with the cover fabric on the teeth, oriented on a bias, with the fabric having a bias angle less than 90°.