The physics in the clutch system is that that the driver depresses the clutch pedal, engages the gear or changes the gear releases the pedal, when increases the speed. This makes for a smooth transition into the already moving vehicle. The clutch starts by allowing the engine power to be given gradually at the start of a vehicle and interrupts the power without having to grinding gears during gear shifting.
Depressing the clutch allows the engine’s power to be transferred to the transmission and drive wheels. Depressing the clutch ceases the power transfer and lets the engine continue rotating without the urge to move the wheels. Basically the clutch system is comprised of the flywheel, clutch disc, pressure plate, throw-out bearing and linkage while some other hydraulic
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which is the best to do

My mech says to change my fly wheel, he will have to remove my engine or drop my gear,
which is best?