Preheat your grill to medium heat.
Rinse the pork ribs and pat them dry with paper towels.
Remove the membrane from the back of the ribs for better flavor absorption.
In a bowl, mix brown sugar, paprika, garlic powder, onion powder, black pepper, salt, and cayenne pepper.
Rub the spice mixture evenly over the ribs.
Place the ribs on the grill bone side down.
Grill the ribs for about 1 hour, turning occasionally.
Brush the ribs with BBQ sauce during the last 20 minutes of grilling.
Check for tenderness; the ribs should be easy to pull apart.
Remove from grill, let rest for 10 minutes, then serve.