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This paper shows the impact of bitrate settings on objective quality measures when streaming non-panoramic remote-rendered Virtual Reality (VR) images. Non-panoramic here refers to the images that are rendered and sent across the network, they only cover the viewport of each eye, respectively. To determine the required bitrate of remote rendering for VR, we use a server that renders a 3D-scene, encodes the resulting images using the NVENC H.264 codec and transmits them to the client across a network. The client decodes the images and displays them in the VR headset. Objective full-reference quality measures are taken by comparing the image before encoding on the server to the same image after it has been decoded on the client. By altering the average bitrate setting of the encoder, we obtain objective quality scores as functions of bitrates. Furthermore, we study the impact of headset rotation speeds, since this will also have a large effect on image quality. We determine an upper and lower bitrate limit based on headset rotation speeds. The lower limit is based on a speed close to the average human peak head-movement speed, 360°s. The upper limit is based on maximal peaks of 1080°s. Depending on the expected rotation speeds of the specific application, we determine that a total of 20--38Mbps should be used at resolution 2160×1200@90,fps, and 22--42Mbps at 2560×1440@60,fps. The recommendations are given with the assumption that the image is split in two and streamed in parallel, since this is how the tested prototype operates., open access