Gearbox ratio 912UL

The 912UL has a dedicated Tachometer signal output on the BLU/YEL and WHT/YEL wires.
This is a One-Pulse-Per-Rev Signal.
If you set the MGL EMS for 1/rev, you should get the correct display.
The MGL Manual contains the instructions.
This is not an analog display. The EMS digitally counts the pulses.
If the display is wrong, it will NOT be slightly wrong, it will be VERY wrong.
If Full power shows anything between 5000 and 6000 rpm, it is probably correct.
If it displays anything under 3000 rpm or over 8000 it is definitely wrong.