What you will need:
1. A leisurely hour of your time (more, if like me you cant find some tools!).
2. A block of wood (prop the tank).
3. Some cable ties (secure sensor wire).
4. Torx drivers (T-handle or socket drivers) T25, 30, 40 and 45.
5. And of course, the Booster Plug!
DISCLAIMER: I'm an amateur (and very average) spanner weilder and not a professional mechanic. This install thread is given in good faith and relates to the original generation 1 bikes (which were the only ones present at the time this DIY was produced). This means that bikes from 2014-2016 should be the same, but later models may differ. Readers use this DIY instruction AT THEIR OWN RISK.
Before you start:
I would recommend you have the fuel tank as empty as possible, I waited till the low fuel light came on. Less weight and less chance of any fuel spillage when you tip the tank.
Lifting the tank
Start by removing the tail hump (or passenger seat) and rider seat to give access to the cast seat brackets.
If you have a BMW tank harness, remove it.
Remove the screws either side of the electrical bus strip. You may have clear washers under the screws (not all bikes seem to have this).
Remove the screw at the end of each seat bracket…
… followed by the screw on top of each seat bracket. Note that there is a washer under the bracket so be sure and save this!
The seat brackets removed.
Remove the cover on the left hand side of the tank that hides the diagnostic socket. Whilst not absolutely necessary (you can reach under the cover to disconnect the socket from it’s holder clip) it does give more access under the tank to install the Booster Plug.
Unclip the diagnostic socket.
Remove the snorkel aluminium cover: Two screws. Note there are clear plastic washers.
There is a rubber snap-lock connector that holds the snorkel panel in place. Gently pull the snorkel cover towards the front of the bike with a slight rocking action and it should come off. Be very careful, you risk damage to the tank, cover or other parts of the bike if the cover comes away suddenly.
The last two screws to be removed before the tank can be raised are the two screws at the front of the tank. BMW recommends that you protect the frame with masking tape (I used insulation tape) and also wrapped the shaft of the T-Handled Torx Driver with a cloth just in case the driver slipped and damaged the tank.
So now its time to pop the hood! Have your piece of wood to hand and gently lift the tank from the front. Once the tank is high enough, slip the wood under the front tank brackets and let the wood rest gently on top of the ignition switch. If the tank is almost empty there will be hardly any weight on the switch as the fuel will be at the rear of the tank where it is pivoting. Take care not to stress the two fuel lines.
Now you have plenty of free space to install the booster plug!
Installing the Booster Plug
Here is the Air Intake Temperature sensor that you will be connecting to….
There is a wire catch that you need to release (push in) to unplug the plug from the AIT sensor.
Now the Booster Plug needs to be connected between the AIT sensor and also the wiring loom socket that originally connected to the AIT sensor plug….
Connected to the loom socket that originally was attached to the sensor…
Then connect the Booster Plug to the AIT sensor.
Almost there! Finally the Booster Plug air temperature probe needs to be positioned. Guidelines advise the sensor gets placed in clear air, outside the influence of engine-generated heat. I chose to mount it at the side of the headstock for loads of fresh air! I cable-tied the sensor cable to the frame.
Now it’s just a case of reversing the tank tilting procedure. Before you lower the tank, double-check that the fuel lines are firmly connected to the tank. Additionally also check that the booster plug wires and control unit do not get trapped by the tank as it is lowered.
I also sprayed the rubber snap-lock (grommet thingy) on the snorkel cover with silicone spray to ease it back onto it's mount.
Job done! Now get out on the bike and marvel at the improvements that a tiny wee box brings to general engine performance and riding pleasure!