See also:

Tachometer
Always avoid engine speeds in the red warning field. In this range, the fuel supply is interrupted to protect the engine. ...

Connecting headphones
You can connect headphones with a jack plug or operate them using the infrared interface. To enable optimal use of the infrared interface, use infrared headphones that comply with the IEC 61603 ...

Tachometer
Never force the engine speed up into the red warning field, see arrow. In this range, the fuel supply is interrupted to protect the engine. ...