Torsional stiffness is a phrase used to describe how easy or difficult it is to twist a ski about the longitudinal axis. Think of wringing out a towel. In the modern age of wide and shapely skis torsional stiffness has become as important as flex used to be. Modern skis turn by bending while on edge. Wide tips and tails grip the snow first and as pressure is applied the ski bends and tends to twist. Twisting causes the ski edge to straighten out and lose a bit of grip. Racers don’t want to lose grip, their skis must be stiff in torsion so the edge continues to bite and maintains its arc. Such skis are precise but all that performance requires a skilled pilot.
Recreational skiers welcome a bit of softness in torsion because that prevents the ski from hooking in, hanging on at the end and behaving aggressively. That’s part of the story in new designs such as Salomon’s Aero series that features Hybrid technology. Hybrid separates the twisting stiffness of the front and back of the ski so engineers can tailor performance more accurately. Skis with torsional softness are referred to as forgiving skis. In each line of skis there is usually a progression of target customers from low to higher ability levels. As performance goes up so does price and that is often due to construction methods and materials. It appears that better materials and more complex constructions are required to make skis that are resistant to twisting. |
