I've owned a 2016 T120 Bonneville for three years and always felt the gearing ratio was a bit high for take-off, around town and countryside riding (low torque). Also, the axle in my bike was always near the back of the swing-arm slot like the OE rear sprocket was too small or the OE chain too long. I changed the rear sprocket from the OE 37 tooth to a larger OD aftermarket 39 tooth. Nice difference. The bike now has more torque "off the line". With the original OE 37 tooth sprocket I was hitting about 3,100 RPM at 70 MPH. The larger 39 tooth rear sprocket gives about 3,250 RPM at 70 MPH. Plus, the rear axle is now nearer the "center" of the swing-arm slot where it should have probably have been all along. No new chain required to go from a 37 tooth to 39 tooth rear sprocket. Acceleration is now livelier but comfort at highway speeds was not compromised. I used a JT Sprocket P/N JTR2014.39.