According to Paradise Wheels, the turning torque of an SN series blower should be 20-25 in.lbs. That caused me to check the unit on my early Avanti since I replaced all the drive parts approx. 3000 miles back. I got 40 in.lbs. Checking the parts books, the early Avantis used load spring 1542958 and plain shim washer 1558157. Later Avantis used 1563153 and no washer. The Hawk/Lark book (green section) lists load spring 1559183 and no washer. Does anyone have the specs. for these springs, or the reason for the differences? Removing the .064" plate washers from my ball load assembly dropped the torque to approx. 30 in.lbs. This is still above the recommended range.