Flexible couplings
Dear F. Yaskin, Thank you for your note. The major reason behind a flexible coupling is transmission protection. In the event the propeller has an impact with something in the water, the flexible coupling will fail verses the transmission taking the full load. A by-product of its flexibility is a reduction of vibration being transmitted through the shaft to the motor. We are very comfortable with the Max-Prop being installed on that transmission without the use of a flexible coupling. If you are in a noise reduction program then I would suggest using it. Moving the shaft aft to a 2” unsupported length is not overly excessive but ABYC does recommend that the distance should not exceed 1.5 times the diameter of the shaft. Before any modification is done to the shaft length I would try it first. If you see a reduction of noise you are ok. If you experience greater shaft whip, remove it and alter the length next time the shaft can be pulled. Hope this helps. Kevin
