Longtail engines are so designed to present the propeller at right angles to the transom giving the maximum thrust without the need for gearboxes etc. The longer the shaft, the closer the prop is to the perfect angle. However the perfect alignment is impossible to obtain using a straight shaft.
Using a tough multi-core steel flexible shaft, a Twister Kit's tail is half the length of a conventional longtail engine, and the prop is perfectly aligned at 90 degrees to the boat, giving more thrust and keeping the boat in perfect trim.
