I have this Yamaha DD-65 drum set. For the high hat and kick drum, there were only small foot switches instead of pedals.
Last year I mentioned to my friends that I needed a MIDI bass drum trigger, but not being musicians, the got together and bought me a normal kick drum pedal for Christmas.
To make it work with the simple switch that came with the DD-65, I used sticky Velcro on the back of the switch and attached it to the side of my Squire BP-15 bass amp.
Works great!