It’s been awhile since I’ve used graphite and I highly recommend learning and using the oil process. But, if your rules state graphite only, make sure you are are using wheel bore polish and polishing the wheel bores per the instructions. After polishing, clean the polish out of the bores with a dish soap solution and a pipe cleaner. Then rinse the wheels out with water. Be careful not to scratch the bore with the wire of the pipe cleaner. Then, add graphite after installing the axle and spin the wheels. Do this over and over several times. The goal is to burnish the wheel bore with graphite. After you assemble the car keep adding graphite and spinning the wheels until race day. If your axles are polished correctly as well, the wheels should spin for a very long time with graphite.