Wag mo lang basta-basta lagyan ng WD40 muna. Try mo muna luwagan yung screw ng expression pedal sa gilid. Usually kasi masikip lang talaga pagkaka-turnilyo n'yan. After mo luwagan, saka mo lagyan ng konting WD40 for lubrication.
Ganyan din 'yung sa 'kin dati. I put some WD40 pero it didn't work. I put some more... still didn't work. I tried loosening the screw a bit... worked like a charm.