I actually just did mine this past week. On the 2016 ZX10R, the O2 sensor plugs in under the tank. You have to get the tank propped up, on the RIGHT side of the bike (brake side) directly behind the air filter housing box you'll see a connector with four wires going into the plug with a sheathing/cover over the wiring. That plug is for the O2 sensor. Pull the wiring gently in either direction with one hand on the wiring AT the O2 sensor itself to put your mind at ease that it is the connector for the O2 sensor. If you look at the manuals posted on the forum I believe there is only one diagram that actually shows where the O2 sensor is located.