Rear suspension for snowmobiles

A snowmobile comprised of a frame assembly, a drive belt having a ground engaging side and a backed-up side, an engine transmission assembly for driving said drive belt, and a suspension system for suspending said drive belt for suspension movement relative to said frame, said suspension system including at least one guide rail associated with the backed-up side of said drive belt for maintaining said drive belt in driving contact with the terrain over which said snowmobile travels, a cushioning unit having a pair of relatively movable end portions and which cushions the movement of the end portions relative to each other, a linkage assembly comprised of links having connections for suspending said guide rail for suspension movement relative to said frame assembly and for loading said cushioning unit by moving the two ends of said cushioning unit relative to each other in opposite directions upon suspension movement, at least one of the connections of said linkage assembly being provided at one end of one of said links being adjustable for adjusting the suspension characteristics of said cushioning unit without changing the relative positions of the ends of the cushioning unit during such adjustment, such adjustment being provided by a slotted connection at the one end of said one link, the radius of said slot being coincident with a pivotal connection at the other end of said one link.

A snowmobile comprised of a frame assembly, a drive belt having a ground engaging side and a backed-up side, an engine transmission assembly for driving said drive belt, and a suspension system for suspending said drive belt for suspension movement relative to said frame assembly, said suspension system including at least one guide rail associated with the backed-up side of said drive belt for maintaining said drive belt in driving contact with the terrain over which said snowmobile travels, a telescopic cushioning unit having a pair of relatively movable end portions and which cushions the movement of the end portions relative to each other, and a linkage assembly comprised of links having connections for suspending said guide rail for suspension movement relative to said frame assembly and for loading said cushioning unit by moving said end portions of said cushioning unit relative to each other in opposite directions upon suspension movement, at least one of the connections of said linkage assembly being adjustable for adjusting the suspension characteristics of said cushioning unit without changing the relative positions of the ends of the cushioning unit during the adjustment, said linkage system including a bell crank having a first pivotal connection to said frame and a second pivotal connection spaced from said first pivotal connection to one of said cushioning unit end portions, a lever pivotally supported on said frame and having a third pivotal connection to the other end portion of said cushioning unit, and a tie bar having a fourth pivotal connection to said bell crank and a fifth pivotal connection to said lever, said second and fourth pivotal connections lying on the opposite sides of said first pivotal connection.