I get that low gears > more power but low speed. I get that high gears >low power but high speed.
But can someone give me the brain dead intuition of why you need to change gear “sizes”? A single sentence if possible.
I’ve tried Googling it but they always use a bike example. I’ve never ridden a bike. Or they start talking about ratios and it just goes over my head.
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The engine is only likes to rotate at certain speeds. So to keep the engine at its happy speed while the car is moving at different speeds you need to change gears
A combustion engine performs better or worse in certain ways at certain RPMs, ***but also***, it can only perform ***at all*** within a certain range of RPMs. If you were to try to drive 10 MPH in 5th gear, the engine would stall because it can’t keep itself running at the super low RPMs that that would require. And if you were to try to drive 100 MPH in 1st gear, the engine would blow itself up because it can’t hold itself together running at such ridiculously high RPMs as *that* would require.
So, the transmission exists to keep the engine spinning within a relatively narrow range of RPMs while allowing a wide range of possible speeds for the vehicle.
A combustion engine performs better or worse in certain ways at certain RPMs, ***but also***, it can only perform ***at all*** within a certain range of RPMs. If you were to try to drive 10 MPH in 5th gear, the engine would stall because it can’t keep itself running at the super low RPMs that that would require. And if you were to try to drive 100 MPH in 1st gear, the engine would blow itself up because it can’t hold itself together running at such ridiculously high RPMs as *that* would require.
So, the transmission exists to keep the engine spinning within a relatively narrow range of RPMs while allowing a wide range of possible speeds for the vehicle.
Consider that your engine can rotate at a range of speeds. Call it 100-1000 rpm (rotations per minute).
If you go faster than that the engine will break. If you go slower it just stops because it can’t sustain itself.
The gears allow you to change the engine rotation to wheel rotation. Gear 1 might say 1 engine rotation = 1 wheel rotation . Gear 2 might say 1 engine rotation = 2 wheel rotation, so if your engine runs at 500rpm the actual car will go twice as fast if you’re in gear 2.
You choose the gear to best match the engine’s rotation speed Vs the speed you want the car to go at.
There’s a bit more to it than just that. But that’s fine for eli5.
If you look at your car dashboard there will be a gauge telling you engine rpm. Probably beside the speed of the car. If you can, take a look at it next time you’re changing gears and see how it moves. (obviously only do so if it’s safe).
Consider that your engine can rotate at a range of speeds. Call it 100-1000 rpm (rotations per minute).
If you go faster than that the engine will break. If you go slower it just stops because it can’t sustain itself.
The gears allow you to change the engine rotation to wheel rotation. Gear 1 might say 1 engine rotation = 1 wheel rotation . Gear 2 might say 1 engine rotation = 2 wheel rotation, so if your engine runs at 500rpm the actual car will go twice as fast if you’re in gear 2.
You choose the gear to best match the engine’s rotation speed Vs the speed you want the car to go at.
There’s a bit more to it than just that. But that’s fine for eli5.
If you look at your car dashboard there will be a gauge telling you engine rpm. Probably beside the speed of the car. If you can, take a look at it next time you’re changing gears and see how it moves. (obviously only do so if it’s safe).
A combustion engine performs better or worse in certain ways at certain RPMs, ***but also***, it can only perform ***at all*** within a certain range of RPMs. If you were to try to drive 10 MPH in 5th gear, the engine would stall because it can’t keep itself running at the super low RPMs that that would require. And if you were to try to drive 100 MPH in 1st gear, the engine would blow itself up because it can’t hold itself together running at such ridiculously high RPMs as *that* would require.
So, the transmission exists to keep the engine spinning within a relatively narrow range of RPMs while allowing a wide range of possible speeds for the vehicle.
Consider that your engine can rotate at a range of speeds. Call it 100-1000 rpm (rotations per minute).
If you go faster than that the engine will break. If you go slower it just stops because it can’t sustain itself.
The gears allow you to change the engine rotation to wheel rotation. Gear 1 might say 1 engine rotation = 1 wheel rotation . Gear 2 might say 1 engine rotation = 2 wheel rotation, so if your engine runs at 500rpm the actual car will go twice as fast if you’re in gear 2.
You choose the gear to best match the engine’s rotation speed Vs the speed you want the car to go at.
There’s a bit more to it than just that. But that’s fine for eli5.
If you look at your car dashboard there will be a gauge telling you engine rpm. Probably beside the speed of the car. If you can, take a look at it next time you’re changing gears and see how it moves. (obviously only do so if it’s safe).
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