According to both the RC8 service manual and the Adventure service manual both bikes require 48 - 54 psi (3.3 - 3.7 bar) for the fuel pumps.
There is a special KTM diagnostic tool to test this but it's computer controlled, password protected, blah blah blah. Sounds like you'd just have to take it into the KTM dealer. Looks like, based on the pictures, that they connect the tool to both the tank and an empty fuel jug. The computer tool actuates the fuel pump to pump fuel through the line from the tank into the jug while a pressure gauge is attached to visually show the pressure. All the computer does, likely, is turn the fuel pump on at a set point (like full throttle or 50% throttle).