Abstract: Disclosed is a pulley having: a shaft; a first shroud, called the fixed shroud, mounted so as to be unable to move in translation with respect to the shaft; a second shroud, called the movable shroud, mounted to be driven in rotation by the shaft but is able to move longitudinally with respect to the latter; a mechanism for mechanically controlling the longitudinal movement of the second shroud with respect to the shaft, having: —a first assembly, which is mounted on the shaft and driven in rotation by the latter, —a second assembly, which is mounted on the shaft by way of at least one torsion spring such that the relative angular position of the second assembly with respect to the shaft depends on the torque transmitted by the shaft, and—a device for locking in at least one position between the first assembly and the second assembly.

Abstract: Disclosed is a solution to the use of a speed limiter in a motorcycle that has a high capacity for acceleration, including a method for limiting the speed of a motorcycle using precise parameters of speed, acceleration and required engine torque and a single control button to manage the smart activation and deactivation of the limiter and to input new speed limits Vlim in a simple way. It thus allows the use of a speed-limiting system in a motorcycle that has a high power/weight ratio by avoiding the sources of interference with the riding and the effects liable to jeopardize its stability.

Abstract: A method for measuring the flow rate MAF of cool air entering an intake manifold of a two-stroke engine, the intake manifold being located between a throttle body and an intake system. The method uses a specific prediction model depending on whether the two-stroke engine is subject, on the one hand, to a light load and, on the other hand, to a medium or heavy load. The model suitable for the load is selected using a predetermined threshold and two absolute pressure measurements taken at the intake manifold at crankshaft angles of rotation around top dead center and bottom dead center. Next, a pressure quotient is formed for each model which will be used to deduce the flow rate of cool air entering the intake manifold.

Abstract: A method for measuring the flow rate MAF of cool air entering an intake manifold of a two-stroke engine, the intake manifold being located between a throttle body and an intake system. The method uses a specific prediction model depending on whether the two-stroke engine is subject, on the one hand, to a light load and, on the other hand, to a medium or heavy load. The model suitable for the load is selected using a predetermined threshold and two absolute pressure measurements taken at the intake manifold at crankshaft angles of rotation around top dead center and bottom dead center. Next, a pressure quotient is formed for each model which will be used to deduce the flow rate of cool air entering the intake manifold.

Abstract: Process for calculating the torque of an internal combustion engine having electronic injection. The method includes having a cogged target with an indexed reference rotating before a fixed sensor. The defects of the target are corrected by distinguishing the combustion interval of the target from the reference. A term assigned to each interval is $g(b)i which is determined in the absence of combustion from the measurement of the engine torque which is proportional to the pressure in the commutator represented by the equation Ci=K.Pcoll=&agr;(&Sgr;N+$g(b)i)N2 where Ci is the engine torque, Pcoll is the pressure, N is the engine power, K is the proportionality factor and &agr; is a constant term.

Abstract: A method for detecting a misfire in at least one truck or motor vehicle internal combustion engine cylinder by analysing the values (Cg, n, i) of a quantity (Cg) characteristic of combustion and generated by observing the rotation of the crankshaft to detect the occurrence of a misfire. According to the method, misfire detection is suspended for a predetermined time when the analysis of said values (Cg, n, i) reveals anomalies originating in the transmission power line between the drive shaft and the vehicle wheels.

Abstract: A method for detecting a misfire in at least one truck or motor vehicle internal combustion engine cylinder by analyzing the values (Cg, n, i) of a quantity (Cg) characteristic of combustion and generated by observing the rotation of the crankshaft to detect the occurrence of a misfire. According to the method, misfire detection is suspended for a predetermined time when the analysis of said values (Cg, n, i) reveals anomalies originating in the transmission power line between the drive shaft and the vehicle wheels.

Abstract: This method includes detecting the passage before a sensor of each of the teeth of the inertial flywheel of an engine; measuring the time of passage d.sub.i of each of these teeth; constituting a measurement horizon extending on both sides of the angular range of the explosions; dividing this measurement horizon into eight sets of teeth of equal length of which six are for the angular range of the explosions; measuring the passage times of these eight sets and in assigning them a rank in the measurement horizon du.sub.+1, du.sub.0, . . . , du.sub.5, du.sub.+1 ; calculating the period of the explosions T=du.sub.0 +du.sub.+1 +du.sub.2 +du.sub.3 +du.sub.4 +du.sub.5 ; calculating a term Q.sub.c =2du.sub.0 -du.sub.-1 -du.sub.3 -du.sub.+1 +2du.sub.5 ; calculating a term D.sub.c =p.multidot.Q.sub.c where p=.pi./2.sqroot.3, a constant stored in a memory; and calculating the desired torque using the relation Cg.sub.c =A.multidot.D.sub.c /T.sup.3 +B/T.sup.2 in which A and B are constants stored in a memory.