ONCE U GET THE MESH RIGHT LOCKTITE THE ENGINE DOWN AND THEY WILL LAST U AWHILE I FAILED TO DO THAT FIRST TIME AND STRIPPED ALL MY GEARS SINCE THE NT-16 VIBRATES PRETTY STRONGLY. I PUT A 1200MAH HPI NICKEL HYDRYDE 5 CELL IN MINE AND IT ROCKS 2-3 HOURS USUALLY BEFORE IT RUNS OUT