I heard a lot of vibration when I went to full throttle with a Tacon Big Foot 25 and the ParkZone BF109G 2-blade spinner on Saturday. The APC 11x8E had already been balanced, so another flyer at the field suggested I also had to balance the spinner. On Sunday, after I separately balanced the back plate and the cone of the spinner, the vibration decreased a great amount at full throttle. I used CA to balance the back plate and Scotch Magic Tape on the inside of the cone to balance the cone. The cone was easy to balance since it had a hole right in the middle of the cone.