Johnson C7000 - Knocking or Creaking Noise

Knocking or creaking noise
Possible causes:
1 Pedal is on crank arm
too loose
2 Crank or axle is wear
out
3 Belt tension is too
loose or poly v belt is
too dirty
4 Rail or roller is too
dirty
Fix:
1 Re-tighten it.
2 Replace it with a new one
3 Re-adjust the belt tension and clean the poly v belt
4 Clean the rail and roller.