Trolling crankbaits...... Burn baby burn. I've been fishing slow and not catch anything and then pick it up as fast as I can reel it and BOMB. Its difficult to hook up running that speed. You'll get a lot of short strikes.... It helps to add a longer trailing treble hook. Never done it from a jet ski but the principle is the same. I generally don't like to do it. The cranks pull so hard at that speed.... you can break a rod... and its difficult to get the other rods in unless you stop.