Lubricate the areas marked in red with little Vaseline or a drop of oil. Clean the trigger with contact spray cleaner. To give more power to the pedal can add a rubber band on the spring, marked in yellow. Enjoy yourself !
Thanks to Jon Bondy\’s site at http://jonbondy.wordpress.com/2012/06/24/fixing-the-roland-hd-1-kick-pedal/
for tricks and photos.