As a Malaysian, I'd eat anything local, but I'd try to skip Nasi Lemak before ride, not because it is not 'sporty' enough for cyclist but because of the sambal that might hurt my stomach. I'd opt for Roti Canai and Teh Halia instead. And sometimes, I'd eat Bee Hoon Goreng or Mee Goreng, if they are available.
And what if you are overly conscious about your calories intake? Then skip Nasi Lemak or Roti Canai, just eat 2 half-boiled egg & plain bread. Hmmm Boring........
During ride, eat simple carbs like sweets, cakes, bread etc. I used to carry biscuits, nuts, raisins or dates for bike tour. Or simply eat bananas which is easy to digest.
After ride, I usually eat Nasi Campur because I love Rice and I need those carbs, and add up with Fish or Chicken for the Protein we need for muscle recovery. And don't forget the junk food like crackers, potato chips, chocolates too.
So, don't worry too much about what to eat. Just enjoy the tour & the food! Bicycle touring will burn out those calories when you ride slow as we usually do, so eat up!