Double-clutching is a method of shifting gears used primarily for vehicles with an unsynchronized manual transmission, such as commercial trucks and specialty vehicles. While double clutching is not necessary in a vehicle that has a synchronized manual transmission, the technique can be advantageous for smoothly downshifting in order to accelerate and, when done correctly, it prevents wear on the synchronizers which normally equalize transmission input and output speeds to allow downshifting.
Heel-and-toe shifting is an advanced driving technique used mostly in performance driving with a manual gearbox, although some drivers use it on the road in everyday conditions in the interest of effectiveness. It involves operating the throttle and brake pedals simultaneously with the right foot, while facilitating normal activation of the clutch with the left foot. It is used when braking and downshifting simultaneously, and allows the driver to "blip" the throttle to raise the engine speed and smoothly engage the lower gear.
An automatic transmission is a multi-speed transmission used in motor vehicles that does not require any input from the driver to change forward gears under normal driving conditions. Vehicles with internal combustion engines, unlike electric vehicles, require the engine to operate in a narrow range of rates of rotation, requiring a gearbox, operated manually or automatically, to drive the wheels over a wide range of speeds.
A manual transmission (MT), also known as manual gearbox, standard transmission, or stick shift, is a multi-speed motor vehicle transmission system, where gear changes require the driver to manually select the gears by operating a gear stick and clutch.
In mechanical or automotive engineering, a freewheel or overrunning clutch is a device in a transmission that disengages the driveshaft from the driven shaft when the driven shaft rotates faster than the driveshaft. An overdrive is sometimes mistakenly called a freewheel, but is otherwise unrelated.
A semi-automatic transmission is a multiple-speed transmission where part of its operation is automated, but the driver's input is still required to launch the vehicle from a standstill and to manually change gears. Semi-automatic transmissions were almost exclusively used in motorcycles and are based on conventional manual transmissions or sequential manual transmissions, but use an automatic clutch system. But some semi-automatic transmissions have also been based on standard hydraulic automatic transmissions with torque converters and planetary gearsets.
Engine braking occurs when the retarding forces within an internal combustion engine are used to slow down a motor vehicle, as opposed to using additional external braking mechanisms such as friction brakes or magnetic brakes.
A direct-shift gearbox is an electronically controlled, dual-clutch, multiple-shaft, automatic gearbox, in either a transaxle or traditional transmission layout, with automated clutch operation, and with fully-automatic or semi-manual gear selection. The first dual-clutch transmissions were derived from Porsche in-house development for the Porsche 962 in the 1980s.
A sprag clutch is a one-way freewheel clutch. It resembles a roller bearing but, instead of cylindrical rollers, non-revolving asymmetric figure-eight shaped sprags, or other elements allowing single direction rotation, are used. When the unit rotates in one direction the rollers slip or free-wheel, but when a torque is applied in the opposite direction, the sprags tilt slightly, producing a wedging action and binding because of friction.
The Yamaha FJR1300A and FJR1300AE/AS are sport touring motorcycles made by Yamaha Motor Company. Both models have a 1,298 cc inline-four engine. The AE/AS model has an electronically controlled clutch and gear shifting system called YCC-S. The clutch and transmissions of the AE/AS models are identical to that of the standard FJR model.
The power band of an internal combustion engine or electric motor is the range of operating speeds under which the engine or motor is able to output the most power, that is, the maximum energy per unit of time. This usually means that maximum acceleration can be achieved inside this band. While engines and motors have a large range of operating speeds, the power band is usually a much smaller range of engine speed, only half or less of the total engine speed range.
A rev limiter is a device fitted in modern vehicles that have internal combustion engines. They are intended to protect an engine by restricting its maximum rotational speed, measured in revolutions per minute (RPM). Rev limiters are pre-set by the engine manufacturer. There are also aftermarket units where a separate controller is installed using a custom RPM setting. A limiter prevents a vehicle's engine from being pushed beyond the manufacturer's limit, known as the redline. At some point beyond the redline, engine damage may occur.
A transmission control unit (TCU), also known as a transmission control module (TCM), or a gearbox control unit (GCU), is a type of automotive ECU that is used to control electronic automatic transmissions. Similar systems are used in conjunction with various semi-automatic transmissions, purely for clutch automation and actuation. A TCU in a modern automatic transmission generally uses sensors from the vehicle, as well as data provided by the engine control unit (ECU), to calculate how and when to change gears in the vehicle for optimum performance, fuel economy and shift quality.
Shift time refers to the time interval between gear changes in a transmission. This interval is the time in which power delivery is transferred to the next selected gear, and engine speed is reduced or increased to synchronize the speed of the next gear. Shift time is usually in reference to motor vehicles, but can apply to any gearbox.
A shift kit is a set of components for automobiles designed to improve how well the car shifts between gears. Kits are made for both automatic and manual transmissions.
Clutch control refers to the act of controlling the speed of a vehicle with a manual transmission by partially engaging the clutch plate, using the clutch pedal instead of the accelerator pedal. The purpose of a clutch is in part to allow such control; in particular, a clutch provides transfer of torque between shafts spinning at different speeds. In the extreme, clutch control is used in performance driving, such as starting from a dead stop with the engine producing maximum torque at high RPM.
Synchronized downshift rev-matching system is a technology invented by Nissan for use on the Nissan 370Z. In combination with the Electronic Control Unit (ECU) and various sensors, the engine electronically blips the throttle for the driver during both downshifts and upshifts to allow for better and smoother shifting, and improved handling.
A motorcycle transmission is a transmission created specifically for motorcycle applications. They may also be found in use on other light vehicles such as motor tricycles and quadbikes, go-karts, offroad buggies, auto rickshaws, mowers, and other utility vehicles, microcars, and even some superlight racing cars.
Car controls are the components in automobiles and other powered road vehicles, such as trucks and buses, used for driving and parking.
The Volvo I-Shift is an automated manual transmission developed by Volvo subsidiary Volvo Powertrain AB for Volvo Trucks and Volvo Buses, with 12 forward gears and 4 reverse gears. It became available for trucks in 2001 and later buses in 2004.
