Abstract: A tunnel for mounting above a road surface (3) comprises a plurality of tunnel segments (1). Each tunnel segment is adapted for mounting at least one projector (6) therein, above a respective opening formed by the tunnel segment in a ceiling of the tunnel. The openings (5) of the plurality of tunnel segments are spaced apart in succession in a direction of travel of vehicles in the tunnel. The tunnel segments are disposed such that projection surfaces (8) of the projectors are seamlessly contiguous or overlapping on the road surface in the direction of travel. The tunnel may comprise awnings positioned at its entrance and its exit, the ceiling being formed at least in part by the awnings. A first awning (10A) may be mounted to a first tunnel segment, in the direction of travel, and a second awning (10B) may be mounted to a last tunnel segment, in the direction of travel.

Abstract: A power pack for a vehicle selected from a group of different vehicles is disclosed. The power pack includes an internal combustion engine and a continuously variable transmission (CVT) operatively connected to the engine. The CVT includes: a drive pulley operatively connected to a crankshaft of the engine, the drive pulley being rotatable about a drive pulley axis; a driven pulley rotatable about a driven pulley axis; a belt connecting the drive pulley to the driven pulley; and a housing at least partly enclosing the drive pulley, the driven pulley and the belt. The power pack also includes a sub-transmission selected from a group of different sub-transmissions depending on the selected vehicle. The selected sub-transmission is mounted to the housing of the CVT. The housing of the CVT is configured to mount any sub-transmission of the group of different sub-transmissions. A method for assembling a power pack is also provided.

Abstract: A method for managing start up of a four-stroke engine, the method being performed by a controller communicatively connected to the engine. The method includes determining, using a crankshaft sensor, an angular orientation of the crankshaft, the crankshaft being rotated by a starter motor prior to ignition of the engine; determining, using the crankshaft sensor, at least one engine speed variation as the crankshaft rotates through at least one measurement window; and identifying a working cycle phase of the crankshaft including in response to an absolute value of the at least one engine speed variation being above a threshold, determining that the crankshaft is in an ignition revolution of a two revolution working cycle of the engine in the measurement window, subsequent ignition of the engine being based on determination of the angular orientation and the working cycle phase of the crankshaft.

Abstract: A method of operating an exhaust valve of a two-stroke internal combustion engine is disclosed. The engine has a cylinder and a piston movably disposed within the cylinder. The cylinder defines at least one exhaust port for discharging exhaust fluid from the cylinder. The exhaust valve is configured to cyclically obstruct the exhaust port. The method includes: rotating the exhaust valve in a first direction for clearing the exhaust port before the piston uncovers the exhaust port during a downstroke of the piston, the first direction being opposite a direction of rotation of a crankshaft of the engine; and rotating the exhaust valve in the first direction for at least partially closing the exhaust port before the piston fully covers the exhaust port during an upstroke of the piston, said rotating of the exhaust valve relative to the rotation of the crankshaft at least partially counterbalancing the crankshaft.

Abstract: A method for controlling a powertrain of a vehicle having a dual-clutch transmission (DCT) includes: operating the DCT while the vehicle is in motion with a high or low transmission gear drivingly engaged; receiving a shift request to engage an other one of the high and low transmission gears; reducing an engine torque output and first and second clutch torques; shifting a subtransmission to a neutral gear setting; selecting a first gear or a second gear to drive the subtransmission; shifting the main transmission to engage the selected first or second gear; after shifting the main transmission, shifting the subtransmission to the other one of the high and low transmission gears; and after shifting the subtransmission, controlling the engine torque output and the first and second clutch torques according to a driver request at an accelerator of the vehicle.

Abstract: A method for controlling an automatic transmission of a vehicle includes: sensing a speed of the vehicle; sensing an acceleration of the vehicle along three spatial axes; determining that the vehicle is in a jump state associated with the vehicle being off a ground surface, the jump state being defined at least in part by the acceleration of the vehicle along the three spatial axes and the speed of the vehicle; and controlling the transmission according to a jump strategy in response to determining that the vehicle is in the jump state. Other methods for controlling an automatic transmission of a vehicle are also contemplated.

Abstract: A method of operating a vehicle is provided. The vehicle includes: an engine; a throttle operator moveable by a driver; a throttle valve regulating airflow to the engine; a continuously variable transmission (CVT) operatively connected to the engine; at least one ground engaging member including at least one of: a wheel and a track; a piston operatively connected to a driving pulley of the CVT for applying a piston force to the driving pulley when actuated and thereby changing an effective diameter of the driving pulley; and a control unit for controlling actuation of the piston and the piston force. The method includes: determining a driven pulley speed of a driven pulley of the CVT; detecting an uphill stand condition indicative of the vehicle being stopped on an uphill; responsive to the detection of the uphill stand condition, controlling the piston force based on the driven pulley speed.

Abstract: An engine assembly for a vehicle includes an internal combustion engine operating on a two-stroke engine cycle. A compressor is in fluid communication with an intake port of at least one cylinder of the engine to pump air into the engine. An exhaust pipe is in fluid communication with an exhaust port of the at least one cylinder. The exhaust pipe has an inlet and an outlet defining a length of the exhaust pipe therebetween. A diameter of the exhaust pipe increases along a portion of the length of the exhaust pipe in a flow direction of the exhaust pipe. The diameter of the exhaust pipe does not decrease along the length of the exhaust pipe in the flow direction of the exhaust pipe.

Abstract: An internal combustion engine has one or more combustion chambers defined by one of more cylinders, corresponding pistons, and a cylinder head. A crankshaft is operatively connected to the pistons and to an electric turning machine. To start the engine, the electric turning machine rotates the crankshaft in a first direction toward a reversal point corresponding to a local maximum drag torque of the internal combustion engine, this rotation being made without rotating the crankshaft beyond the reversal point. The electric turning machine then rotates the crankshaft in a second direction opposite from the first direction, a momentum impressed on the crankshaft by compression obtained when rotating in the first direction increasing a speed of the crankshaft in the second direction. Thereafter, fuel is injected in one of the combustion chambers in which the corresponding piston first reaches a top dead center position and the fuel is ignited.

Abstract: A turbine wheel for a turbine of a turbocharger. The turbine wheel includes a plurality of turbine blades distributed evenly about the axis of rotation; and a plurality of inter-blade portions distributed evenly about the axis of rotation. Each of the inter-blade portions is disposed between two blades and each of the blades is disposed between two inter-blade portions, the inter-blade portions and the turbine blades being integrally formed. A cross-section, taken along a plane normal to the axis of rotation, of a surface of each inter-blade portion of the plurality of inter-blade portions being described by a smooth curve extending between the two turbines blades of the plurality of turbine blades between which the inter-blade portion is disposed. In some cases, the smooth curve of each inter-blade portion is described by a curve fitted to a biomimicry design form extending between the first blade and the second blade.

Abstract: A valve for use in an engine exhaust conduit. The valve includes a base portion and a body portion extending from the base portion. The base portion is configured for pivotably mounting the valve within the engine exhaust conduit. The base portion defines a valve pivot axis. The valve is pivotable about the valve pivot axis during use. The body portion has an upstream side and a downstream side opposite the upstream side. The upstream side is exposed, during use, to fluid flow in the engine exhaust conduit. The body portion has a generally pointed shape defining a rounded tip at a location of the body portion furthest from the base portion in a length direction of the valve. The length direction of the valve is generally perpendicular to the valve pivot axis.

Abstract: An engine assembly for a vehicle includes an engine and a turbocharger operatively connected thereto. A controller is configured to, based on at least one performance parameter associated with the vehicle, execute a pre-acceleration control sequence including: delaying ignition within the engine's cylinders to increase a temperature of exhaust gas discharged to the turbocharger and reduce a torque of the engine; deactivating at least one cylinder in a predetermined pattern to reduce the torque of the engine; actuating a throttle valve to increase air flow to the engine to (i) increase the torque of the engine, and (ii) increase a volume of exhaust gas discharged to the turbocharger; and increasing a volume of fuel injected by the fuel injectors into the cylinders so as to increase the torque of the engine thereby compensating at least in part reduction of the torque of the engine.

Abstract: A method for inverting a rotation of an impeller driven by a motor of a watercraft is disclosed. In response to sensing that the motor is stopped, a direct linkage is disconnected between the motor and the impeller and a reverse connection is established between the motor and the impeller. The motor is started after sensing that the reverse connection is established. A watercraft propulsion system having an electronic control unit configured to perform the method and a watercraft including the watercraft propulsion system are also disclosed. Reverse operation of the impeller is useful in removing debris from the jet propulsion system.

Abstract: A transmission includes a first shaft with two gears adapted for connecting to a motor and a second shaft with two corresponding gears adapted for connecting to a driveshaft; a shift drum selectively controlling torque transfer between the shafts and defining therein two grooves; a shift rod translatable along a rod axis with a driving member fixedly connected thereto and engaging one groove, at least a portion of the groove causing the driving member and the shift rod to translate along the rod axis upon rotation of the shift drum; an engagement dog disposed on the second shaft for selectively engaging the gears of the second shaft; two biasing members disposed around the shift rod; a fork rod supporting a shift fork slidably connected to the fork rod and the shift rod, the shift fork being engaged in another groove of the shift drum.

Abstract: A method of operating a vehicle having an engine, a throttle valve and a throttle operator. A continuously variable transmission operatively connected to the engine has a driving pulley, a driven pulley, and a belt operatively connecting the driving and driven pulleys. A ground engaging member is operatively connected to the driven pulley. A piston is operatively connected to the driving pulley for applying a piston force thereto and thereby changing an effective diameter of the driving pulley. A control unit controls actuation of the piston and the piston force. The method includes detecting a stall condition indicative of the vehicle being stalled, and, responsive to the detection, setting the piston force to be zero.

Abstract: A two-stroke internal combustion engine has a crankshaft disposed at least in part in a crankcase, and a cylinder block connected to the crankcase and defining a cylinder. The cylinder defines at least one exhaust port for discharging exhaust fluid. A piston is movably disposed within the cylinder and is operatively connected to the crankshaft. The piston is movable along a cylinder axis in a reciprocating motion including an upstroke and a downstroke. An exhaust valve assembly is operatively connected to and rotates with the crankshaft. The exhaust valve assembly has a shaft rotatably supported by the cylinder block and a valve configured to cyclically obstruct the exhaust port. The valve is operable to move clear of the exhaust port before the piston uncovers the exhaust port during its downstroke, and at least partially close the exhaust port before the piston fully covers the exhaust port during its upstroke.

Abstract: An electric kart has a frame, a seat, four wheels, an electric motor operatively connected to two of the wheels, and at least one battery operatively connected to the electric motor. The at least one battery has a support structure mounted to the frame of the electric kart, and battery cells positioned on the support structure such that there is at least one air passage defined between the battery cells. Air passes through the at least one air passage when the electric kart is in motion to cool at least some of the battery cells. A battery for an electric kart is also disclosed.

Abstract: A turbocharger for an engine includes a housing, a shaft, a turbine wheel mounted to the shaft for rotation therewith, a compressor wheel mounted to the shaft for rotation therewith, and a bearing cartridge rotatably supporting the shaft relative to the housing. The housing is positioned axially between the turbine and compressor wheels. The bearing cartridge includes an inner ring mounted to the shaft, an outer ring disposed between the inner ring and the housing and movable relative to the housing, and a first and a second plurality of roller elements axially spaced apart from one another and disposed radially between the inner and outer rings to rotatably support the inner ring relative to the outer ring. A radial gap (RD) is defined between the outer ring (134) and the housing (126). Lubricant flows into the radial gap and radially separates the outer ring from the housing during operation of the turbocharger.

Abstract: A kart includes a frame, front and rear wheels rotatable about front and rear axle axes, and an impact protection structure surrounding the frame. The impact protection structure includes: at least one front protective element, at least one rear protective element, and at least one lateral protective element on each lateral side of the kart. Each of the at least one lateral protective element is mounted to a pivot bearing fixed to the frame so as to be pivotally adjustable about a frame vertical axis, and is disposed closer to the rear axle axis than to the front axle axis. Each of the pivot bearings includes a bearing block and a bearing pedestal pivotable relative to the bearing block. Each of the at least one lateral protective element engages the bearing pedestal of a corresponding pivot bearing. Shock-absorbing dampers are disposed between the frame and the protective elements.