Data set supports figures 3, 5 and 6 of the published manuscript "Bacterial flagellar motor as a multimodal biosensor". Folder "Figure 3": "Traces": Contains .txt files with Fourier transform (rotational speed) of bead coordinates for 1 Wild type (WT) cell, and 4 mutant strain (delCheZ) cells. Time is given in seconds, speed in Hz. Folder also contains .txt file with data format explanation. The traces were used to calculate biases plotted in figure 3B. 3B_Biases.xlsx: Points used for plotting figure 3B. Bias was calculated from the traces described above with 5 second sliding window. Biases are given for 4 delCheZ cells and 1 WT cell. Folder "Figure 5": "5C traces": folder contains .txt files (1 file for an individual cell) with rotational speed (in Hz) sampled at 100 points per second rate. Folder also contains .txt file with data format explanation. Individual traces were used for calculating mean trace with the standard deviation plotted in Fig. 5C. 5B and 5C points.xlsx: Points used for plotting figures 5B and 5C (individual traces for 5B were kindly provided by Dr. Ashley Nord). Normalised mean speed is given. Folder "Figure 6": Contains points used for figure 6. CW and CCW speed in Hz is given for different experimental buffers and bead sizes (indicated in left column).