MotorCycle game: Motorcycle drives itself (2D)

Hey there,
So ive been working on a 2D motorcycle game where you as a player need to drive over a track including jumps and certain trick spots.

I was working on the script for the motor and I got it error free, but when i hit the play button the motor drives itself without me pressing the forward key(W).

Check the uploaded file for the script

Please help, i am new to unity and this is the first project where i am actually making progress.
Any other tips would also be welcome!