Abstract: A two-stroke internal combustion engine including a molded ignition housing connected to the crankcase of the engine which protects the electric generator of two-stroke internal combustion engine.

Abstract: A family of snowmobiles having different tunnel widths is disclosed. A snowmobile having spacers between the tunnel and the sides of the engine compartment and a method of manufacturing such a snowmobile are also disclosed. A snowmobile having a countershaft which is disposed rearwardly of the engine, vertically higher than the air intake opening, and forwardly of the air intake controller is also disclosed.

Abstract: A snow vehicle includes a track belt unit having an endless track belt, an engine arranged to drive the track belt unit, a steering mechanism to which a pair of steerable skis positioned in a forward direction of the track belt unit and being steerable to the left and right are attached, and a handlebar section coupled to the steerable skis via the steering mechanism and adapted to be gripped by a rider. The handlebar section and the rear end of the cylinder head are in generally the same position in a longitudinal direction of the snow vehicle.

Abstract: A snow vehicle includes a track belt unit having an endless track belt, an engine arranged to drive the track belt unit, a steering mechanism to which a pair of steerable skis positioned in a forward direction of the track belt unit and being steerable to the left and right are attached, a rod-shaped steering shaft coupled to the pair of steerable skis via the steering mechanism, a rod-shaped handlebar section coupled to the steering shaft and adapted to be gripped by a rider, and a pair of left and right footrests which allow the rider to rest the rider's feet thereon. A straight line that is perpendicular or substantially perpendicular to a longitudinal direction of the steering shaft extends from an upper end of the steering shaft to each footrest, as seen in a side view of the snow vehicle.

Abstract: A snowmobile having a double A-arm front suspension is disclosed. The double A-arm front suspension includes an upper A-arm, a lower A-arm, and a spindle connecting the skis the upper A-arms and lower A-arms, the connection of the upper and lower A-arms to the spindle define a caster angle, the upper A-arm and the lower A-arm are connected to the front portion of the frame such that the caster angle decreases when the front suspension is compressed. Also disclosed is a snowmobile having a suspension travel of at least 8 inches and a steering assembly having a single pitman arm.

Abstract: A two-stroke internal combustion engine including a molded ignition housing connected to the crankcase of the engine which protects the electric generator of two-stroke internal combustion engine.

Abstract: A snowmobile is disclosed having improved drive train including a continuously variable transmission (CVT) having a drive belt looped around a driving pulley and a driven pulley, and a transversely arranged jackshaft wherein the driven pulley is connected directly onto the outer surface of one end of the jackshaft. The transverse jackshaft is preferably made from a thin-walled hollow tube and the driven pulley is preferably press fitted thereon. A method of assembling a snowmobile drive train is also disclosed.

Abstract: A snowmobile includes a seat having a rear end with a rear end face. The rear end face is inclined upwardly and rearwardly from an upper surface of a tunnel of a frame so that a cavity is defined beneath the seat between the inclined rear end face of the seat and the upper surface of the tunnel.

Abstract: A rear track suspension for a snowmobile having a single resilient element for biasing both the front and rear arms. The slide rail is permitted to pitch between first and second pitching constraints in response to terrain obstacles in a gradual manner as the motion constraints are approached. This reduces jarring of the rider when the pitching constraints are met. Suspension compression exhibits an initial falling rate motion ratio, followed by a constant rate motion ratio, followed by a rising rate motion ratio. This U-shaped motion ratio profile advantageously provides cushioning upon landing along with a resistance to bottoming out of the suspension upon full compression. The result is an improved ride without sacrificing suspension performance.

Abstract: A power management system for a snowmobile is provided to efficiently manage power supplied to a cooling fan and to a heater on the snowmobile. The power management system can be incorporated into a control unit of the snowmobile and can be comprise of a fan motor control section for activating the fan motor by supplying electric power from a generator (or a battery). The fan motor control section operates the fan motor in various operating conditions in accordance with the value detected by a temperature sensor associated with a fluid cooling system of the snowmobile's engine. The power management system can also include a heat control section for controlling the electric power supplied by the generator (or a battery) to the heater by adjusting it in accordance with such parameters as maximum power levels associated with preset temperature settings or variable temperature settings, an engine speed sensor signal, and the operating condition of the fan motor.

Abstract: An adjustable seat for a snowmobile has a base having an upper sitting portion for accommodating a driver and a slidable coupling for sliding the seat relative to a chassis of the snowmobile. The seat is movable between a forward position and a rearward position. Threaded fasteners or other connectors are employed to secure the adjustable seat to the chassis in an ergonomic position. The adjustable seat thus accommodates drivers of different height and/or drivers who adopt different postures when riding by comfortably seating the driver on the sweet spot of the seat regardless of the driver's height or his driving posture.

Abstract: A snow remover for removing snow lying upon an inner surface of an endless drive track of a snowmobile includes a mounting portion and a scraping portion. The snow remover of the present invention is to be attached to a stationary structure of the snowmobile such that the scraping portion extends towards the inner surface of a lower section of the endless drive, to scrape off snow. Thus, this portion of snow is prevented from being thrown onto the riders of the snowmobile.

Abstract: A snowmobile straddle seat assembly designed to accommodate one, two or three riders. The seat may have a continuous surface including three seating positions thereon or it may include separate seat portions where the separate seat portions may be selectively removed to provide storage space and a variety of seat configurations.

Abstract: A frame assembly is described including a tunnel, an engine cradle disposed forward of the tunnel and connected thereto, and a sub-frame disposed forward of the engine cradle and connected thereto. A forward support assembly extends upwardly from the subframe. An upper column extends upwardly from the engine cradle to connect with the forward support assembly. A rear brace assembly extends upwardly from the tunnel to connect with the forward support assembly and the upper column. In one embodiment, the frame assembly further includes an engine disposed in the engine cradle. An endless track is operatively connected to the engine and disposed beneath the tunnel for propulsion. A pair of skis is operatively connected to a steering device for steering. In another embodiment, the frame assembly further includes an engine disposed in the engine cradle.

Abstract: The specification herein discloses a tracking control system for a vehicle such as a snowmobile. Such a vehicle includes a chassis with at least one ride member, such as a ski. The tracking control system includes a suspension arm, a spindle, and a slide bar. The suspension arm extends outwardly from the chassis, the arm being pivotally secured to the chassis. The spindle is secured to an outward end of the suspension arm. The spindle has an upper end a lower end with the slide bar secured to the lower end. The slide bar is oriented generally transverse to the spindle and to a major axis of the ski. The ski is movably coupled to the slide bar and spring biased in a direction away from the chassis.

Abstract: The present invention is directed to an air box assembly for a snowmobile. The air box assembly is capable of being positioned frontward of the snowmobile engine, relative to a front end of the snowmobile. In this position, throttle noise being dampened by the air box assembly is further removed from an operator of the snowmobile sitting in an operator position on the snowmobile.

Abstract: A snowmobile comprises a left-right pair of skis, an engine and a track belt provided on a vehicle body. The track belt is driven by the engine, and the skis are steered by an operation on a steering handlebar. The vehicle body frame is formed by connecting intermediate frame sections, which are U-shaped in side view, to a front portion of a rear frame section, the rear frame section having a roughly U-shaped section and connecting a front frame section to front portions of the intermediate frame sections. In the vehicle body frame, detachable side frame sections are used to connect the portions between the upper ends of front suspension members for supporting the skis and a front portion of a rear cushion for supporting the track belt. The reinforcing side frame sections include portions which are protuberant to the upper side and curved downwards, respectively. The resulting snowmobile frame structure is rigid enough to accommodate an engine of increased weight.

Abstract: A snowmobile includes a nose cone having an underbelly, first and second side walls and a top cover together defining a substantially conical enclosure for enclosing a forward end of the snowmobile. The top cover includes a pair of air inlets for admitting air into the engine compartment as well as air guides connected to the inlets for directing the air to desired regions of the engine compartment for improving engine performance. The top cover also includes grilles for filtering out snow and other debris. Furthermore, the air guides are designed to suppress engine noise.

Abstract: An integrated heat exchanger and engine mount for a snowmobile that reinforces the snowmobile chassis is disclosed. The heat exchanger is formed with an internal passage through which a vehicle fluid may be circulated and cooled. The heat exchanger is also formed with increased rigidity to strengthen the chassis and support an engine mount.

Abstract: An improved component layout in a snowmobile includes a muffler is disposed on the front side of an engine, and a lower portion of a steering shaft extends between the muffler and the engine. The engine is disposed rearwardly of the lower portion of the steering shaft. In other words, the steering shaft lower portion is disposed on the front side of the engine, whereby the engine is easily relocated rearwards with respect to the vehicle body so as to concentrate the center of mass at a central location of the vehicle body.

Abstract: An adjustable storage seat for recreation and utility vehicles is disclosed. The adjustable storage seat may be used for snowmobiles, watercraft, all-terrain vehicles, or other similar small vehicle intended for entertainment and transportation. The adjustable storage seat comprises a cushion mounted over a frame which is attached to the chassis of the vehicle. The seat is provided with an adjustable backrest which can be adjusted forward or backward in increments to increase the comfort of the rider when a button on the seat is pushed, but otherwise remains fixed in place. The adjustable backrest can also be removed from the seat to reveal a storage compartment after turning it 90 degrees. The seat may be provided with a lock to secure the storage compartment. Additional embodiments of the adjustable storage seat are convertible for one or two person use, and may be provided with internal storage or item racks.

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. In another aspect of the invention, the rear of the tunnel is connected to a molded rear member. The rear member provides a downwardly curving back portion for the tunnel. The rear member may have a shape corresponding to that of the tunnel, e.g. 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, thereby permitting snow thrown by the endless track to pass on both sides of the heat exchanger. In another aspect of the invention, a tunnel for a snowmobile may be narrower in the front than in the rear.

Abstract: A vehicle comprises a frame and a slide rail disposed below the frame for guiding a drive track along a road surface. An arm has a first portion pivotally coupled to the frame at a frame pivot location and a second portion pivotally coupled to the slide rail at a rail pivot location. Vertical movement of the slide rail causes a length of the arm between the frame pivot location and the rail pivot location to extend or contract. The vehicle suspension system becomes increasingly stiffer as the deflection of the slide rail increases, to contribute to a more comfortable ride and to reduce the risk of bottoming-out.

Abstract: A vehicle including a frame, a seat attached to the frame front section for supporting the driver in a sitting position, a protective shell attached to the frame front section for substantially enclosing the driver and a pair of skis for gliding on a supporting surface. The skis are pivotally attached to the frame front section substantially laterally on each side of the cabin. The skis are coupled to a steering wheel located in the cabin by a steering assembly for allowing the driver to steer the vehicle by pivoting the skis relative to the frame. The vehicle also includes a propelling assembly having an endless track operatively mounted to the frame rear section rearwardly relative to the seat for contacting the supporting surface and propelling the vehicle. A motor is mounted on the frame rear section in a substantially overlying and proximal relationship relative to the endless track. The motor is operatively coupled to the endless track for driving the latter.

Abstract: A traction runner for a snow ski is fabricated of a lightweight metal such as aluminum and is formed on its upper surface with a channel in which mounting members are fixed. A channel is formed also in the lower surface and a carbide wear strip is brazed through induction heating to the aluminum runner body.

Abstract: A snowmobile four-cycle engine arrangement, includes: a four-cycle engine arranged in an engine compartment formed in the front body of a snowmobile with its crankshaft laid substantially parallel to the body width and having a cylinder case inclined forwards with respect to the vehicle's direction of travel. The engine employs a dry sump oil supplying system and an oil tank separate from the engine is provided. Another snowmobile four-cycle engine arrangement includes: a four-cycle engine having a cylinder head at its top, arranged in the engine compartment and inclined forwards with respect to the vehicle's direction of travel with an intake path provided on the upper portion of the engine body. An intercooler for cooling the intake air is arranged in a tunnel created inside the body frame for accommodating a track belt.

Abstract: A snowmobile throttle control apparatus includes a pair of bushings with a hole and closed ends and a separate axle pin. The bushings are assembled to a thumb lever and mounted over the axle pin. The axle pin allows for a controlled gap to be maintained between the throttle lever, bushing assembly and the control housing. The thumb lever is allowed to flex open when a side load is applied. Thus allowing the thumb lever assembly to travel without binding on the control housing. This insures proper functioning of the RPS feature.

Abstract: To apply special contrivances to the structure and layout of a reserve oil tank disposed on the front side of a dry sump type internal combustion engine mounted on a snowmobile, thereby to achieve effective utilization of space in the snowmobile, and to achieve a further reduction in the size of the snowmobile. A reserve oil tank is laid out on the front side of a dry sump type internal combustion engine mounted on a snowmobile, and the layout of the tank is so made that a tank wall in the longitudinal direction crosses the engine front side. The tank is provided in a tank front wall in the longitudinal direction thereof with an arcuate recessed groove extending vertically in the tank, and a steering shaft vertically passes through the inside of the recessed groove.

Abstract: A vehicle comprises a frame and a slide rail pivotally coupled to the frame. A spring member urges the slide rail in a direction away from the frame. The spring member has a first portion mounted to the frame and a second portion supported on the slide rail at a first spring support position in a first configuration. A spring support is coupled to the vehicle at a second spring support position and is arranged to engage the spring member upon deflection of the slide rail in a second configuration. The vehicle suspension system becomes increasingly stiffer as the deflection of the slide rail increases, to contribute to a more comfortable ride and to reduce the risk of bottoming-out.

Abstract: A snowmobile is provided that includes a frame, an engine, an endless belt drive system, and an air intake system for the engine. The frame has a forward portion and an aft portion. The engine is mounted to the forward portion and the belt drive system is mounted to the aft portion and is operatively connected to the engine. The engine is a turbocharged four-stroke type engine.

Abstract: A snowmobile rear suspension is shown comprised of a linear force element (LFE) positioned outside the envelope of the snowmobile endless track. The snowmobile frame includes a chassis mounted to a tunnel, where the chassis includes a central mounting bracket. The LFE is attached at one end to the bracket and at the other end to a bell crank. The bell crank is operatively connected to the slide rails. When the slide rails collapse in normal operation, the bell crank strokes the LFE, and the suspension is progressive throughout the range.

Abstract: A snow vehicle includes an engine, a track belt arranged on a rear side of the engine, and a cooling water path for cooling the engine, in which the engine includes a cooling water inlet portion and a cooling water outlet portion provided on a front surface side of the engine and connected with the cooling water path. The snow vehicle is capable of improving the turning ability of the vehicle, while simplifying a cooling water path and reducing the size of the structure for cooling the engine.

Abstract: A snowmobile steering mechanism adapted to place higher pressure on the outside ski than on the inside ski when the snowmobile enters and exits turns, said steering mechanism being adapted to include the suspension in the steering action of the snowmobile causing the snowmobile to automatically lean into a turn improving the ability of the snowmobile to enter and exit turns in comparison to a snowmobile without the inclusion of the suspension in the steering action of the snowmobile.

Abstract: A snowmobile with an intercooler includes a four-stroke-cycle engine unit disposed in an engine room covered by an engine hood, and the engine unit includes an engine body, a turbocharger, an intercooler for cooling an intake-air, which is pressurized and heated up by the turbocharger, and an electric motor-driven cooling fan provided for the intercooler for introducing an outside air to the intercooler through which the air after cooling the intercooler is discharged toward the inside of the engine room.

Abstract: A vehicle, such as a snowmobile, includes an engine with one or more air intakes for receiving air into the engine and an airbox for directing air into the air intakes. The airbox slides to facilitate installation and removal of the airbox from the engine compartment, which thus economizes time and cost both for vehicle assembly and maintenance. The sliding airbox also eliminates the need for a gap between the fuel tank and the airbox, allowing the fuel tank to be moved forward, thus improving mass centralization of the vehicle. The sliding airbox has a rectangular slot which slides onto a rectangular plate on an intake adapter. The intake adapter has a flexible tubular connection for each cylinder of the engine which are secured to each air intake with a hose clamp. The air intake usually includes an air metering device such as a carburetor or throttle body.

Abstract: A snowmobile positions riders close to the center of gravity of the snowmobile, reduces jostling forces, and improves the comfort and ridability of the snowmobile. The snowmobile has a steering position on a steering device that is disposed forward of the forward-most drive axle and center of gravity of the snowmobile. A steering shaft, which operatively connects the steering device to the skis, forms an angle of less than 45 degrees with vertical. The seat may have seat positions for one, two, or three riders, the first seat position being disposed less than 590 mm behind the forward-most drive track axle. The seat may be divided into two sections, the second seat section being removably attached to the frame behind the first seat section. The back of the seat and the rearward-most seat position may be disposed behind the back end of the snowmobile's frame.

Abstract: A snowmobile four-cycle engine arrangement, includes: a four-cycle engine arranged in an engine compartment formed in the front body of a snowmobile with its crankshaft laid substantially parallel to the body width and having a cylinder case inclined forwards with respect to the vehicle's direction of travel. The engine employs a dry sump oil supplying system and an oil tank separate from the engine is provided. Another snowmobile four-cycle engine arrangement includes: a four-cycle engine having a cylinder head at its top, arranged in the engine compartment and inclined forwards with respect to the vehicle's direction of travel with an intake path provided on the upper portion of the engine body. An intercooler for cooling the intake air is arranged in a tunnel created inside the body frame for accommodating a track belt.

Abstract: A steering post for use with a recreational vehicle, particularly a snowmobile or ATV, is described. The steering post includes a steering shaft having upper and lower ends; at least two steering arms, the two steering arms being positioned at an angle to a longitudinal axis of the steering shaft; a ball joint assembly positioned at the lower end of the steering shaft; and a stop. An upper bearing for supporting a steering post on a recreational vehicle may have a radiused inner surface that can accept some misalignment of the shaft. A steering system also can include a double ball joint linkage that permits an easier and simpler adjustment of the steering system. A recreational vehicle such as snowmobile or ATV making use of these features also is described.

Abstract: A snowmobile four-cycle engine arrangement, includes: a four-cycle engine arranged in an engine compartment formed in the front body of a snowmobile with its crankshaft laid substantially parallel to the body width and having a cylinder case inclined forwards with respect to the vehicle's direction of travel. The engine employs a dry sump oil supplying system and an oil tank separate from the engine is provided. Another snowmobile four-cycle engine arrangement includes: a four-cycle engine having a cylinder head at its top, arranged in the engine compartment and inclined forwards with respect to the vehicle's direction of travel with an intake path provided on the upper portion of the engine body. An intercooler for cooling the intake air is arranged in a tunnel created inside the body frame for accommodating a track belt.

Abstract: A front suspension system for a recreational vehicle such as a snowmobile has a lower A-arm assembly and an upper suspension arm for connecting each front ski to the chassis of the recreational vehicle. The lower A-arm restrains the front ski from moving backward or laterally while the upper arm connects to the top of the spindle to ensure that the spindle remains substantially vertical when the front ski encounters a bump.

Abstract: A frame assembly is described including a tunnel, an engine cradle disposed forward of the tunnel and connected thereto, and a sub-frame disposed forward of the engine cradle and connected thereto. A forward support assembly extends upwardly from the subframe. An upper column extends upwardly from the engine cradle to connect with the forward support assembly. A rear brace assembly extends upwardly from the tunnel to connect with the forward support assembly and the upper column. In one embodiment, the frame assembly further includes an engine disposed in the engine cradle. An endless track is operatively connected to the engine and disposed beneath the tunnel for propulsion. A pair of skis is operatively connected to a steering device for steering. In another embodiment, the frame assembly further includes an engine disposed in the engine cradle.

Abstract: A lubricant tank for a lubrication system of a snowmobile engine includes an upper portion and a lower portion. The upper portion is enlarged relative to the lower portion. A recess is defined on an engine side of the lubricant tank by a lower surface of the upper portion and a lateral surface of the lower portion. The recess accommodates a protruding portion or component of the engine. The tank also comprises a sloping surface that extends between the upper portion and the lower portion inside the tank. Lubricant is returned in the upper portion and transferred to the lower portion through a zigzag flow path.

Abstract: A snow cycle includes a conventional motorcycle chassis having a set of steerable front forks and a rear swing arm, which normally mount front and rear wheels of the cycle, respectively. A snow track module is mounted to the rear swing arm and has an endless track driven by a cog connected to a drive sprocket of the engine by a single chain. At least one and preferably a pair of skis are mounted off the front forks and are pivotable fore and aft as well as tiltable to either side to maintain the ski flat to the ground when the vehicle is tilted to one side or the other when making an aggressive turn.

Abstract: A snowmobile with arrangement of a four cycle engine is disclosed providing a relatively low center of gravity for improved handling and maneuverability. The engine comprises a cylinder unit slanted to the back of the snowmobile and an improved packaging of auxiliary components in order to optimize the location of the center of gravity on the snowmobile. The engine has a balancer shaft rotatably coupled to the crankshaft and the balancer shaft axis is positioned above the crankshaft axis.

Abstract: A isolation unit for a snowmobile connects to the forward frame members of the snowmobile and provides a plurality of receptacles and mounting points for receiving and securing various front-end components to the snowmobile. The isolation unit not only facilitates assembly and maintenance of the snowmobile but also protects and isolates vibration-sensitive components from the vibrations of the engine. The isolation unit is molded from plastic to accommodate a variety of components, including a hood, a console, a headlight, an ignition coil, fuel tank vent pipe, stepper motor, a km/MPH converter, an electrical wire harness, an electronic control unit, an exhaust pipe temperature sensor wires, a fuse box, an engine reverse buzzer, and a capacitor.

Abstract: A snowmobile including a chassis, shell, and an engine. The shell may be fixed to a front portion of the chassis and extend away from the chassis in a forward direction. The shell may be disposed forward of the steering axis. The shell may define a chamber that fluidly communicates with the engine via a flexible coupling interposed between the shell and the engine.

Abstract: The present invention provides a handlebar tilting apparatus having upper and lower pivotally attached brackets, a lever, and appropriate connectors to fasten the brackets and lever to each other in accordance with the present invention. In the embodiment shown and described herein, the brackets each adopt a generally U-shaped configuration with opposing side members and a transition member extending therebetween and integral therewith. The lower bracket is stationary and is attached to the steering column of a vehicle using a handlebar for steering. The upper bracket is attached to the handlebar of the vehicle. The lever is pivotally attached to the upper bracket by a lever pin and supports a latch pin that selectively engages notches disposed in the lower bracket.

Abstract: In a snowmobile, an upper front half of a vehicle body of the snowmobile is covered to be openable by an engine hood in which an engine room is defined, an engine is disposed in the engine room, and a turbo-charger is mounted on the engine. In an engine structure of such snowmobile, a headlight is disposed above a rear portion of the engine hood, and the engine is arranged in a state inclined rearward downward so that a cylinder head of the engine is disposed below the headlight in a side view and the turbo-charger is arranged below the cylinder head.

Abstract: Suspension wheels, or bogie wheels, in an endless track vehicle are longitudinally offset, or staggered, from one another in such a way as to cause the track rods of the endless track to impact only one suspension wheel at any given point in time.

Abstract: A snowmobile includes an improved internal combustion engine. The engine comprises a crankcase, a crankshaft rotatably journaled within the crankcase, a cylinder block assembly extending from the crankcase, and a cylinder head assembly connected to an end of the cylinder block opposite the crankcase. A cam drive mechanism including at least one camshaft is rotatably journaled within the cylinder head assembly. A transmission is coupled to the crankshaft to transmit power from the engine to the drive assembly. The cam drive mechanism is connected to the crankshaft at a first end portion of the crankshaft. The transmission is connected to the crankshaft at a second end portion of the crankshaft opposite the first end portion.