Abstract: A replacement bumper for a snowmobile ski is provided and methods for using the same. The replacement bumper has an abutment surface that makes contact with a spindle of a snowmobile in order to increase the contact surface area of a rear portion of a snowmobile ski and the ground and/or increase the weight being distributed on the rear portion of the snowmobile ski, which prevents the darting or tracking of the snowmobile ski. Also, includes is a method for removing an OEM bumper from a snowmobile ski assembly and installing a replacement bumper into said snowmobile ski assembly.

Abstract: A rotary cutter and end bit therefore is provided for cleaning and clearing debris and roots from a pipe. The cutter comprises a support housing having a plurality of radially extending skid fins, which help position the chain root cutter in the center of the pipe. The support housing carries a rotor and the rotor rotates relative thereto. A motor supported by the support housing is adapted to rotate the rotor. A plurality of linkages extends radially from the rotor and attaches at least one end bit to the rotor of the chain root cutter. The end bit comprises a hard wear resistant material, such as carbide, that faces radially outward and increases the wear life of the end bit. The wear resistant material may comprise carbide chips that continuously provide sharp edges over the life of the end bit.

Abstract: A wear rod for a snowmobile ski is provided that contains multiple wear edges. The wear rod includes a longitudinally extending host bar having longitudinally extending grooves. Strips of a harder second material are integrally mounted in the grooves to increase the wear resistance of the wear rod. The strips define wear edges that contact the trail surface as the snowmobile turns or moves in a straight direction. The wear edges are located such that as the snowmobile ski turns, the wear rod cants and a portion of the load of the snowmobile shifts from one wear edge to another wear edge. The wear edges are also arranged such that the wear edges are self-sharpening to maintain the functional life of the wear rod.

Abstract: A snowmobile ski built from strips of plastic to selectively form the bottom contour on the ski body of the snowmobile ski. The strips of plastic may be used to build a new ski or rebuild/reconstruct an existing snowmobile ski that has a center keel. The snowmobile ski comprises mounting shoe for mounting the snowmobile ski to the snowmobile and a longitudinally extending plastic ski body having an upwardly curved front tip toward the front end. The strips of plastic include a pair of plastic side pads. The side pads are removably secured to the bottom surface of the ski body and extend longitudinally along the ski body. The strips of plastic may also include a removable center keel. A wear bar or wear rod assembly may be fastened to the center keel.