That SK3 motor should be fine for a smaller diameter weapon like a drum or a small disk, maybe not enough power for a larger diameter. As long as you gear the motor down, it will probably be fine to over-volt the motor on a 6S pack to get a more power out of it; power will be almost 1.6Kw on 22.2V. With a 2:1 belt reduction and running on 22.2V, the no-load speed at the weapon is a respectable 7,000 rpm.