Abstract: An idler wheel assembly, for example a rear idler wheel assembly, for a snowmobile and includes at least one cross-member that permits load transfer and possible load damping as between a pair of rear idler wheels. The cross-member may be configured to transfer lateral loads, bending loads and other types of loads between the idler wheels. The cross-member is arranged between the wheels in such a manner that it is free to rotate with the idler wheels without interference to or from other structure of a skid frame assembly of the snowmobile. In one embodiment, each idler wheel includes a cross-member that extends inward to connect to the other wheel.

Abstract: A snowmobile chassis includes dual panels that form a lighter weight and stronger tunnel preferably without the need for structural doublers, plates or other attachable reinforcement devices. The dual panels take the form of inner and outer panels coupled together with selective gaps or spaces located between the panels. The gaps laterally separate the panels and may be continuous and take a variety of shapes as defined by each panel's configuration. The arrangement of the gaps may advantageously define a desired structural load path through the tunnel, increase a section modulus with respect to a centerline of the tunnel, and reduce an overall weight of the tunnel as compared with conventional tunnels that utilize added reinforcement devices.

Abstract: An idler wheel assembly, for example a rear idler wheel assembly, for a snowmobile and includes at least one cross-member that permits load transfer and possible load damping as between a pair of rear idler wheels. The cross-member may be configured to transfer lateral loads, bending loads and other types of loads between the idler wheels. The cross-member is arranged between the wheels in such a manner that it is free to rotate with the idler wheels without interference to or from other structure of a skid frame assembly of the snowmobile. In one embodiment, each idler wheel includes a cross-member that extends inward to connect to the other wheel.

Abstract: A snowmobile chassis includes dual panels that form a lighter weight and stronger tunnel preferably without the need for structural doublers, plates or other attachable reinforcement devices. The dual panels take the form of inner and outer panels coupled together with selective gaps or spaces located between the panels. The gaps laterally separate the panels and may be continuous and take a variety of shapes as defined by each panel's configuration. The arrangement of the gaps may advantageously define a desired structural load path through the tunnel, increase a section modulus with respect to a centerline of the tunnel, and reduce an overall weight of the tunnel as compared with conventional tunnels that utilize added reinforcement devices.

Abstract: The top wall of a snowmobile tunnel, which accommodates the endless drive track of the snowmobile, is provided with recesses at locations corresponding to the path followed by studs carried by the endless track. The rear of the tunnel is connected to a molded rear member having a pattern of recesses matching that of the top wall of the tunnel. In yet another aspect of the invention, a heat exchanger for cooling engine coolant may be provided at the rear of the tunnel. The heat exchanger may be mounted to and partially spaced from the molded rear member. The heat exchanger may bear rearwardly extending ridges with upwardly extending lip at the far end. In some embodiments, a channel is provided on the upper end of the heat exchanger to promote air and snow flow over the rearwardly extending ridges.

Abstract: The top wall of a snowmobile tunnel, which accommodates the endless drive track of the snowmobile, is provided with recesses at locations corresponding to the path followed by studs carried by the endless track. The rear of the tunnel is connected to a molded rear member having a pattern of recesses matching that of the top wall of the tunnel. In yet another aspect of the invention, a heat exchanger for cooling engine coolant may be provided at the rear of the tunnel. The heat exchanger may be mounted to and partially spaced from the molded rear member. The heat exchanger may bear rearwardly extending ridges with upwardly extending lip at the far end. In some embodiments, a channel is provided on the upper end of the heat exchanger to promote air and snow flow over the rearwardly extending ridges.