G1 adaptive clearing slow feedrate

Hello,
I'm having trouble with slow feedrate when using G1 command for adaptive clearing operation.
What exactly happens:
I generate adaptive clearing path in Fusion 360.
Drillbit enters the material via ramp command G3 at the feedrate of 1000 (displayd at the controller) which corresponds to the feedrate set in the code F1000.
When G1 command begins (also set at the feedrate of 1000) the machine slows down to the feedrate of ~450-600..
I thought it might be acceleration problem but the slow down is really visible and the acceleration is much lower than when performing the G3 ramp entrance.
Then I thought it might be a problem of sharp angles of the path as a result of low approximation of the curves.
The approximation in the adaptive clearing was set to 0,1.
When I increased the approximation to 0,01 (more control points in the code)
The machine slowed down even more to the feedrate of ~200...
This is all very strange.
Especially because when I use G1 command for the parallel operation the feedrate is correct.