eli5 why ev car can’t make manual transmission. the real manual transmission that have clutch and so on.?
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Think of the gears on a bicycle, they exist because there’s a limit to how fast and slow you can pedal. Different gears allow you to pedal at a specific pace, but gain different speeds from that pace.
An electric engine can “pedal” as fast or slow as needed, so gears have no use. Transmission in an EV car would kinda be like wheels on a hot air balloon, solving a problem that doesn’t exist.
Think of the gears on a bicycle, they exist because there’s a limit to how fast and slow you can pedal. Different gears allow you to pedal at a specific pace, but gain different speeds from that pace.
An electric engine can “pedal” as fast or slow as needed, so gears have no use. Transmission in an EV car would kinda be like wheels on a hot air balloon, solving a problem that doesn’t exist.
Think of the gears on a bicycle, they exist because there’s a limit to how fast and slow you can pedal. Different gears allow you to pedal at a specific pace, but gain different speeds from that pace.
An electric engine can “pedal” as fast or slow as needed, so gears have no use. Transmission in an EV car would kinda be like wheels on a hot air balloon, solving a problem that doesn’t exist.
They could, but they don’t need to so why do it.
Internal combustion engines have what’s known as a “power band”. Basically the engine makes very little power under (around) 1500 RPM with the ideal power starting at 2500 (ish). That’s why you need to rev up the engine before shifting into first, because if you don’t the engine will stall.
Internal combustion engines also generally don’t love going above 6,000-7,000 RPM (depending on the particular engine) and often stop making their best power around 5,000 RPM. There’s issues with heat and friction that cause this. Often race car engines can go a lot higher, but that’s pretty rare.
So for an ICE car they typically want to stay between 2500 and 5000 RPM regardless of what speed the car is going. The transmission’s main job is to ensure that regardless of how fast the wheels are going, the engine is always between 2500 and 5000 RPM.
An electric motor does not have this “power band” nor do they stall. So with an electric car you get full force from 1 RPM all the way up. Speaking of up, sice electrical motors do not contain explosions they do not generate as much heat. Also because they do not have pistons they don’t rub metal against metal. So that means that they don’t have the same RPM cap as an ICE car would.
A tesla drive unit can go from 1 to (about) 16,000 RPM and be perfectly happy at any point along the way. There’s no reason for a transmission.
They could, but they don’t need to so why do it.
Internal combustion engines have what’s known as a “power band”. Basically the engine makes very little power under (around) 1500 RPM with the ideal power starting at 2500 (ish). That’s why you need to rev up the engine before shifting into first, because if you don’t the engine will stall.
Internal combustion engines also generally don’t love going above 6,000-7,000 RPM (depending on the particular engine) and often stop making their best power around 5,000 RPM. There’s issues with heat and friction that cause this. Often race car engines can go a lot higher, but that’s pretty rare.
So for an ICE car they typically want to stay between 2500 and 5000 RPM regardless of what speed the car is going. The transmission’s main job is to ensure that regardless of how fast the wheels are going, the engine is always between 2500 and 5000 RPM.
An electric motor does not have this “power band” nor do they stall. So with an electric car you get full force from 1 RPM all the way up. Speaking of up, sice electrical motors do not contain explosions they do not generate as much heat. Also because they do not have pistons they don’t rub metal against metal. So that means that they don’t have the same RPM cap as an ICE car would.
A tesla drive unit can go from 1 to (about) 16,000 RPM and be perfectly happy at any point along the way. There’s no reason for a transmission.
They could, but they don’t need to so why do it.
Internal combustion engines have what’s known as a “power band”. Basically the engine makes very little power under (around) 1500 RPM with the ideal power starting at 2500 (ish). That’s why you need to rev up the engine before shifting into first, because if you don’t the engine will stall.
Internal combustion engines also generally don’t love going above 6,000-7,000 RPM (depending on the particular engine) and often stop making their best power around 5,000 RPM. There’s issues with heat and friction that cause this. Often race car engines can go a lot higher, but that’s pretty rare.
So for an ICE car they typically want to stay between 2500 and 5000 RPM regardless of what speed the car is going. The transmission’s main job is to ensure that regardless of how fast the wheels are going, the engine is always between 2500 and 5000 RPM.
An electric motor does not have this “power band” nor do they stall. So with an electric car you get full force from 1 RPM all the way up. Speaking of up, sice electrical motors do not contain explosions they do not generate as much heat. Also because they do not have pistons they don’t rub metal against metal. So that means that they don’t have the same RPM cap as an ICE car would.
A tesla drive unit can go from 1 to (about) 16,000 RPM and be perfectly happy at any point along the way. There’s no reason for a transmission.
They can, they have, and there are some planned to come out in the future. The original Tesla and the Porsche Taycan had a tow gear gear box. A few conversions have also left the clutch attached to the original manual transmission and it works fine.
The fact is, they just don’t need it – and extra weight means decreased range – so out it goes.
But, why doesn’t an electric require a transmission and clutch?
Transmission: When a gas engine runs too slow, it dies. When it runs too fast, it can overheat or break. This range of RPMS (how fast its running) is surprisingly narrow. A transmission allows the ratio of wheel speed to engine speed to change to stay in this narrow range (this is why modern CVTs are so efficient, the V is for “variable” as it can set whatever the appropriate ratio is, like an infinite number of gears without the added weight.) An electric engine, however, can run at max speed or a complete crawl without too much issue. Additionally, a lot of “AWD” electrics can house two motors – one running the front, another running the back wheels, and each “geared” differently to be more efficient at higher or lower speeds, and then adjusting where the car’s power goes based on what is needed (for instance, the front wheels may be more efficient at higher speeds, while the rear gives more power at lower speeds and shuts off at highway speeds for maximum efficiency).
Clutch: The clutch is there to disconnect your driveshaft from the engine. In a gas car, this prevents the car from stalling if the speed of the wheels gets too slow for the engine to run. You then choose an appropriate gear for your speed and adjust the engine’s RPMs to the appropriate speed to drop the clutch back into gear. Remember, an electric engine doesn’t stall at slow speeds and can run REALLY fast – so this just isn’t necessary, you could just shift gears with an electric (and in fact a few race cars were setup this way).
IN the end though, the whole gear system does have a loss of energy in it. You want your engine as directly connected to the wheels as you can, and adding gears and clutches is moving in the opposite direction while not adding anything.
That said, there are rumors of a few companies planning on including a shifter in some high-end electric cars – but it would probably just be a gimmick as opposed to a mechanical advantage.
As a weird side note: EVs don’t need a reverse gear. The engine can just run in reverse. So, unlike a gas powered car, an EV (technically) can drive as fast backwards as it can forwards.
They can, they have, and there are some planned to come out in the future. The original Tesla and the Porsche Taycan had a tow gear gear box. A few conversions have also left the clutch attached to the original manual transmission and it works fine.
The fact is, they just don’t need it – and extra weight means decreased range – so out it goes.
But, why doesn’t an electric require a transmission and clutch?
Transmission: When a gas engine runs too slow, it dies. When it runs too fast, it can overheat or break. This range of RPMS (how fast its running) is surprisingly narrow. A transmission allows the ratio of wheel speed to engine speed to change to stay in this narrow range (this is why modern CVTs are so efficient, the V is for “variable” as it can set whatever the appropriate ratio is, like an infinite number of gears without the added weight.) An electric engine, however, can run at max speed or a complete crawl without too much issue. Additionally, a lot of “AWD” electrics can house two motors – one running the front, another running the back wheels, and each “geared” differently to be more efficient at higher or lower speeds, and then adjusting where the car’s power goes based on what is needed (for instance, the front wheels may be more efficient at higher speeds, while the rear gives more power at lower speeds and shuts off at highway speeds for maximum efficiency).
Clutch: The clutch is there to disconnect your driveshaft from the engine. In a gas car, this prevents the car from stalling if the speed of the wheels gets too slow for the engine to run. You then choose an appropriate gear for your speed and adjust the engine’s RPMs to the appropriate speed to drop the clutch back into gear. Remember, an electric engine doesn’t stall at slow speeds and can run REALLY fast – so this just isn’t necessary, you could just shift gears with an electric (and in fact a few race cars were setup this way).
IN the end though, the whole gear system does have a loss of energy in it. You want your engine as directly connected to the wheels as you can, and adding gears and clutches is moving in the opposite direction while not adding anything.
That said, there are rumors of a few companies planning on including a shifter in some high-end electric cars – but it would probably just be a gimmick as opposed to a mechanical advantage.
As a weird side note: EVs don’t need a reverse gear. The engine can just run in reverse. So, unlike a gas powered car, an EV (technically) can drive as fast backwards as it can forwards.
They can, they have, and there are some planned to come out in the future. The original Tesla and the Porsche Taycan had a tow gear gear box. A few conversions have also left the clutch attached to the original manual transmission and it works fine.
The fact is, they just don’t need it – and extra weight means decreased range – so out it goes.
But, why doesn’t an electric require a transmission and clutch?
Transmission: When a gas engine runs too slow, it dies. When it runs too fast, it can overheat or break. This range of RPMS (how fast its running) is surprisingly narrow. A transmission allows the ratio of wheel speed to engine speed to change to stay in this narrow range (this is why modern CVTs are so efficient, the V is for “variable” as it can set whatever the appropriate ratio is, like an infinite number of gears without the added weight.) An electric engine, however, can run at max speed or a complete crawl without too much issue. Additionally, a lot of “AWD” electrics can house two motors – one running the front, another running the back wheels, and each “geared” differently to be more efficient at higher or lower speeds, and then adjusting where the car’s power goes based on what is needed (for instance, the front wheels may be more efficient at higher speeds, while the rear gives more power at lower speeds and shuts off at highway speeds for maximum efficiency).
Clutch: The clutch is there to disconnect your driveshaft from the engine. In a gas car, this prevents the car from stalling if the speed of the wheels gets too slow for the engine to run. You then choose an appropriate gear for your speed and adjust the engine’s RPMs to the appropriate speed to drop the clutch back into gear. Remember, an electric engine doesn’t stall at slow speeds and can run REALLY fast – so this just isn’t necessary, you could just shift gears with an electric (and in fact a few race cars were setup this way).
IN the end though, the whole gear system does have a loss of energy in it. You want your engine as directly connected to the wheels as you can, and adding gears and clutches is moving in the opposite direction while not adding anything.
That said, there are rumors of a few companies planning on including a shifter in some high-end electric cars – but it would probably just be a gimmick as opposed to a mechanical advantage.
As a weird side note: EVs don’t need a reverse gear. The engine can just run in reverse. So, unlike a gas powered car, an EV (technically) can drive as fast backwards as it can forwards.
That would be totally useless. My Tesla can go from 0-155 MPH using a single simple reduction gear. Adding a clutch or transmission would add hundreds or thousands of additional parts for absolutely no benefit.
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