Fewer than 3% of cars sold in the U.S. have manual transmissions • Hacker News Board

Re: Fewer than 3% of cars sold in the U.S. have manual transmissions

#741

Post by user5994461 » Thu, Nov 17, 2016, 6:50 PM UTC

gens wrote: post #727

sshanky wrote: post #128

Earlier quoted context omitted.

In modern cars, disengaging the clutch (or using neutral) when coasting (toward a stop or down a hill) is less efficient than staying in gear. This is because it takes some fuel to keep the engine idling, where staying in gear allows the computer to completely cut fuel flow, as long as the forward motion is keeping the engine turning.

There is nothing preventing cars with manual clutches from doing that. People going down hills with manual transmission also keep the car in gear (they teach you that). And it doesn't matter as it is not much fuel compared to the fuel used when accelerating, where automatic transmissions are less efficient. If that is the only reason for automatic transmission to be more efficient, then i doubt it is.

> People going down hills with manual transmission also keep the car in gear (they teach you that).

It's taught for safety reasons. You have more controls of the car with the motor attached.

Re: Fewer than 3% of cars sold in the U.S. have manual transmissions

#742

Post by Bartweiss » Thu, Nov 17, 2016, 6:50 PM UTC

at-fates-hands wrote: post #588

JoeAltmaier wrote: post #562

Earlier quoted context omitted.

Just what the previous commentor said: saves on wear and tear on the brake pads. As for wear on the engine: the engine is actually designed to mesh with the transmission. Engine braking is not much different than accelerating.

>> Just what the previous commentor said: saves on wear and tear on the brake pads. When I was learning how to drive a manual, my Dad was a huge fan of them and all of our family cars were manual. I was taught that it makes a huge difference when you're driving in the mountains to use engine braking instead of your brakes. He also explained the difference in braking in traffic and using engine braking to do so and ho…

The point about gas is certainly true, thought I can't speak to the rest as much.

While you're accelerating, you're giving the engine gas to keep it moving and prevent a stall. While braking you aren't accelerating, but you still need the engine to keep going at speed.

If you depress the clutch, it disconnects the engine from the wheels. The engine will then get a trickle of gas (even if you don't accelerate) to keep it moving while the car breaks.

If you don't depress the clutch, the engine stays in connection with the wheels. Their motion drives the engine - the reverse of normal - keeping it moving without burning any gasoline at all.

It's not generally a big difference, but if you're in the hills of Colorado you might care more.

Re: Fewer than 3% of cars sold in the U.S. have manual transmissions

#743

Post by mikestew » Thu, Nov 17, 2016, 6:52 PM UTC

emodendroket wrote: post #510

capkutay wrote: post #265

Earlier quoted context omitted.

I also drove a manual while commuting about 70 miles a day on the freeway. I figured out that you can make manual driving as comfortable and carefree as automatic, but that type of driving typically wears on the clutch. For instance, you might just hold down the clutch in stop/go traffic if you don't know if you'll change gears or not. I was even pretty proficient at using my phone while driving with a manual but onc…

To the contrary, I find just popping it into neutral frequently is a much more comfortable way of handling stop-and-go than holding down the clutch all the time.

Do it right, and you don't even need to engage the clutch. Right when you let off the gas, pull the lever to neutral. If you're really good, and you're still rolling, you can give the throttle a little blip and put it right back into first w/o any clutch.

Re: Fewer than 3% of cars sold in the U.S. have manual transmissions

#744

Post by schwap » Thu, Nov 17, 2016, 6:53 PM UTC

TeMPOraL wrote: post #433

geff82 wrote: post #165

Manual transmission is not somehow cool, it just shows the inefficiencies of a regular gas engine more openly: that the engine has to run in a certain small band of RPM to provide the energy for driving. Automatic transmission covers the deficiency best - and will be the standard on the electric car future ahead. In that way, Americans are already used to the future.

I don't get why you're downvoted, it's exactly the case - the very need for having a gearbox is a problem of ICEs. Electric engines don't have gears because the RPM/efficiency curve is pretty much flat.

Aren't there still benefits to running at lower speeds? Electric motors aren't magic frictionless devices, higher speeds must still produce increased wear and heat.

Re: Fewer than 3% of cars sold in the U.S. have manual transmissions

#745

Post by mikestew » Thu, Nov 17, 2016, 6:55 PM UTC

barsonme wrote: post #736

forgetsusername wrote: post #439

Earlier quoted context omitted.

> I was very surprised at how much torque the car had. The torque curve on EVs is awesome for sure; I can't wait to own one. But I'll bet that most people have never driven a ICE car with any real power or an automatic transmission tuned for acceleration as opposed to gas mileage. They also "take off" with minimal lag.

Oh yeah. I drive a 2000 Toyota Corolla, so even a Camry is 'fast' to me. I just have to convince the SO to let me purchase a motorcycle...

I just have to convince the SO to let me purchase a motorcycle...

And thereby ruining cars for you forever. Oh, your $250K McLaren does 0-60 in three seconds? Yeah, so does my $10K bike.

It does save you money on cars, though. With two bikes in the garage, we're content to drive slow compacts when we need four wheels.

Re: Fewer than 3% of cars sold in the U.S. have manual transmissions

#746

Post by mmagin » Thu, Nov 17, 2016, 6:56 PM UTC

CoffeeDregs wrote: post #650

aleh wrote: post #582

Earlier quoted context omitted.

When breaking with engine, the kinetic energy of movement is converted to heat not via friction (like breaks do) but via compressing air in cylinders which does not cause extra wear on anything.

I think you're referring to "Jake Braking", which is very noisy and is banned in many towns (in California). https://en.wikipedia.org/wiki/Compression_release_engine_bra...

At least the manufacturers of those products assert that correctly installed ones are no louder than the diesel engine in normal operation.

http://www.jacobsvehiclesystems.com/about-us/environmental-h...

Re: Fewer than 3% of cars sold in the U.S. have manual transmissions

#747

Post by mmagin » Thu, Nov 17, 2016, 6:57 PM UTC

sshanky wrote: post #128

vmarsy wrote: post #104

Earlier quoted context omitted.

>when automatic transmissions are consistently outperforming humans at fuel efficiency Do you have data to back this up? Unless you're driving a dual clutch "dry" transmission or a CVT, because of Physics, an automatic transmission will always be less efficient. The Automatic transmission Torque converter [1] will waste some of the energy provided by the engine, especially with city driving. Also, most automatic cars…

In modern cars, disengaging the clutch (or using neutral) when coasting (toward a stop or down a hill) is less efficient than staying in gear. This is because it takes some fuel to keep the engine idling, where staying in gear allows the computer to completely cut fuel flow, as long as the forward motion is keeping the engine turning.

Yep. Where modern in some cases includes cars from 26 years ago. (My 1990 Chevy Corsica - inline 4, with a single throttle-body injector did this.)

Re: Fewer than 3% of cars sold in the U.S. have manual transmissions

#748

Post by penglish1 » Thu, Nov 17, 2016, 6:58 PM UTC

Just one more reason to get a motorcycle. Or two. Maybe three. Did you know you can fit several motorcycles in the same space as just one car in your garage?

Also, I feel compelled to point out that you can get a Porsche, or Lotus or whatever and feel pretty cool with your francy sports car. Or you can get _several_ top of the line motorcycles for the same price. Just sayin'

Re: Fewer than 3% of cars sold in the U.S. have manual transmissions

#749

Post by fnj » Thu, Nov 17, 2016, 6:59 PM UTC

kps wrote: post #581

Aaargh20318 wrote: post #319

Earlier quoted context omitted.

> Purely from logic, your claim has to be false: Imagine a humanoid robot sitting in your driver's seat, driving your manual transmission car, its robot arm doing the shifting exactly as a human would. Your manual car has been turned into an automatic and it is not less efficient. You're forgetting a very important factor: the automatic transmission can only respond to the drivers actions. Unlike the driver it has no…

> It will happily shift up 2 seconds before I hit the brakes because > it has no idea I'm planning to take a left turn in 20 meters. Purely hypothetically, a car could be fitted with an operator control to convey that sort of intent. It could be something the driver could operate without taking their hands off the wheel — perhaps a stick on the left of the steering column?

You already have one of those. If you are driving a 4-speed automatic, you can see that you are in 3rd and sense that it might be about to upshift and a turn is coming up, you can whip it from D to 3 to hold it in 3rd for the duration.

Re: Fewer than 3% of cars sold in the U.S. have manual transmissions

#750

Post by mjevans » Thu, Nov 17, 2016, 6:59 PM UTC

ohyoutravel wrote: post #472

pryelluw wrote: post #432

Earlier quoted context omitted.

This is one of my pet peeves. Sometimes I use left foot braking to transfer chassis weight from one side to tve other. Having a throttle cut off sucks. I won't buy a car with it anymore.

I can't think of any situation outside of a race course where this would be a necessary maneuver. If you're going so fast on public roads where you need to left foot brake to transfer weight to avoid skidding off the road, it sounds like something is wrong. Where are you doing this enough where having a car with throttle cut off is enough of an annoyance where you won't buy a car with it anymore? For reference, I got…

I'm not downvoting you, but I disagree with your line of reasoning.

Just because YOU don't see why a feature might be useful does not mean that it isn't useful. It just means you don't see a use for it.

Similarly, while cutting the fuel on break application might be useful or even beneficial in the case of a normal / particularly bad driver (slamming down all the peddles in an emergency) it does mean a drastic change in the human/machine interface. I would say that just like ABS is a good safety feature and airbags / restraint belts are good safety features, the vehicle should CLEARLY MARK these features. Their automation may (EG as in the cases of baby seats) be counter-intuitively less safe in circumstances.