Melt butter in a large nonstick skillet over medium-high heat. Add pecans; sauté 1 minute. Add bananas; sauté 2 minutes. Drizzle with 1/3 cup syrup; cook 1 minute. Remove from heat.
Spoon about 1/3 cup banana mixture into the center of each crepe. Fold sides and ends over. Place on a serving platter, seam sides down; drizzle with remaining syrup.