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Short / On the move
A running engine meets the load of a stationary car. This short focuses on the moment the clutch engages and why engine speed can collapse.
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As a manual car moves off, its engine is already rotating while the gearbox side of the clutch starts from rest. Releasing the pedal quickly can build clutch torque abruptly. If the engine cannot sustain that load, its rotational speed can drop until it stalls.
In the dry-clutch example, the contacting surfaces can rotate at different speeds while friction transfers torque. This allows the gearbox side to speed up before the clutch becomes fully coupled. The Short concentrates on this transition; the full explanation follows the flywheel, disc and pressure plate.
Continue with the full 2:05 clutch explanation
No. The result depends on engine speed, available torque, the load and how the clutch engages.
Its friction surfaces are transmitting torque while still rotating at different speeds. During take-up, that bridges the speed difference.
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