Yamaha DTXpress/DTXplorer/DTXtreme

Double peddles work fine with the ETXpress II.  I am likewise 
learning to do double bass after many years of not playing drums.  
There are lots of exercises on the net (see www.drumbum.com), and 
some suggest doing the rudiments with your feet vs your hands as a 
strategy.  Keep practicing, as it is just starting to come together 
for me after several months of constant effort.

Doc