Tall apes are a great look on custom choppers, but the leverage they generate can lead to bar slip inside old or tired two-piece risers. Our Thunder riser combats this problem by adding clamping power and surface area around the handlebars. Thunder riser's one-piece design enhances stiffness in the top tree to reduce lateral twist. NOTE: If your motorcycle has removable bar clamps and its top tree accepts 1/2-inch O.D. mounting hardware, our Thunder riser should fit, but only if the mounting hole centers on your tree are 3.5 inches apart.