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Balancing Throttle Bodies on the ST
On the Speed Triple Ive always used th Morgan Carbtune to balance the throttle bodies.
Using the carbtune on the 1050ST engine with the Kehien ECU will give incorrect results and it needs to be done via the plug in dealertool or a tool such as TUNEECU of TuneBoy.

You will need a laptop and a USB cable with the connector for the FDTI connector.
Latest version of the free open source TUNEECU is always avalable from here
Latest version of the very expensive Tubeboy always avalable from here

I use TuneECU

You will need to buy a USB cable with an FTDI chip in it. DO a search for Tuneboy or TuneECU cable on Ebay and you will find loads.
I found a short length of 3x2 positioned against the sub frame allows the rear of the tank to sit perfectly. Supporting it without fouling the connections and allowing enough room to carry out any adjustments.
Assuming the drivers for the cable are all installed on your laptop:

Connect the FTDI cable to the loom port found sitting in the right glove box space.
Connect to the laptop.
Start TuneECU
turn on ignition.
Start engine
Allow engine to warm up
Open garage door coughing guts up
Swap TuneECU to the tests page. The three smaller dials show the pressure in each throttle body.

Blip the throttle and see where they settle to.
Mine are not far out, but they are out.
Synch TB2 to TB1.
Make half a turn then blip the throttle and see where it settles.
Do it again with a half turn at a time until Tb and TB2 are exactly matched.
You can see how the throttle body pressures are linked.
Matching TB1 and TB2 has knocked TB3 further out.
Now repeat the process with TB3
You will probably need to adjust TB 2 and 3 again as they get close until all three TB's are perfectly matched.
Take your time to get it as perfect as possible.
When done, no matter how hard you blip the throttle, all three TB's will settle into a perfect match every time
The airbox needs to be off. So do this as part of a service when the airbox will be off anyway.

With the airbox off reconnect the tank. You can use a remote connection kit or as I have done here.