[Reason077]

Modern manual cars have start/stop technology too.

However, it's more convoluted to use. You have to engage the clutch, put the shifter in neutral, and release the clutch again. Compared to automatic where you just have to hold your foot on the brake pedal.

Stop/start reduces fuel consumption on test cycles like NEDC for both automatics and manuals, but I'll bet in the real world the benefit is mostly seen with automatics as many manual drivers will rarely bother to use it.

[edoloughlin]

However, it's more convoluted to use. You have to engage the clutch, put the shifter in neutral, and release the clutch again

This is how you should drive if you know you're going to be stopped for more than a few seconds. 'Convoluted' doesn't come into it - it's the default.

[Reason077]

I've driven manuals most of my life. Before stop/start came along, I was in the habit of just holding the clutch pedal down while stopped at intersections or in traffic. Anecdotally, I think most drivers do the same.

Now, when driving stop/start equipped vehicles, I always try to use it. But in a manual, it does takes more thinking and effort and I wonder how many casual drivers actually bother.

The thing is, most of the time you don't really know how long you're going to be stopped for. Will that light take 3 seconds or 30? A manual makes you decide whether to stop the engine, but an automatic just does it every time without having to think about it or perform extra steps. (although, you can override it if you know it's going to be a short stop by just pressing the brake lightly.)

[djsumdog]

I drove a WRX for five years and the clutch was kinda heavy. Not terrible, but enough that I'd put the car I'm neutral at a red light of I was there for more than five seconds.

I'm glad start stop is supported on manuals this way. It makes sense. I thought the stop start systems didn't really save much fuel, but I've read some real world tests that clock in at 8~10% savings. All that idle time does really add up.

[blub]

I consider holding the clutch down really unusual. Never did myself except when I was pretty sure that start/stop would trigger unnecessarily.

Now I just don't care about that, since it was too annoying at stop lights, which has led to incidents of auto-stop and immediate start and even a half auto-stop. Didn't notice and bad effects on the car.

[mnw21cam]

> I was in the habit of just holding the clutch pedal down while stopped at intersections or in traffic.

If you take a driving test in the UK and do this, that would be a minor fault. You can only have a few minor faults before you fail the test. The rationale is that you need to be in full control of the car at all times, and when you set off you mustn't drift backwards at all. The easiest way to do this without needing three legs is to use the handbrake. Unless you have a diesel engine that has enough torque without any pressure on the accelerator pedal to pull away.

[JetSetWilly]

There's lots of minor faults that don't reflect how people actually drive.

For example if you are turning right and waiting for oncoming traffic to clear, then someone pauses and flashes their lights to let you turn, if you then turn that would be a minor fault in Driving Test conditions - where you are supposed to ignore the driver inviting you to turn and sit like a diddy.

Also you are allowed 15 minor faults before failure, which is quite a lot really.

[Reason077]

Huh? Whether or not you put the shifter in neutral has no effect on handbrake (hill) starts. You can still (more quickly, in fact) perform a hill start without also having to put the car back in gear.

And now days, newwer cars have the "hill hold" feature which automatically prevents you rolling backwards anyway.

[Annatar]

Before stop/start came along, I was in the habit of just holding the clutch pedal down while stopped at intersections or in traffic. Anecdotally, I think most drivers do the same.

I usually keep my foot to the side, as I was explicitly taught in driving school by a professional instructor to do. And if the master cylinder ever starts to malfunction, since the plate spacing is really tight, keeping the clutch pedal depressed while stopped could prematurely burn up the clutch and the torque plate.

[JoeAltmaier]

Its called 'riding the clutch'. But all you have to do to avoid the wear is keep it fully depressed. End of moralizing.

[Shorel]

I don't hold the clutch for too long because that will increase the effort from my left foot, and I don't like how it feels after a week of driving that way.

So, it may require more thinking, but I can rest my feet while the light is red and it actually feels good.

[vetinari]

By holding down the clutch pedal, you are literally destroying the clutch. When I was in the driving school, I was taught to never do this. If you are stopping, even for just few seconds, put in the neutral. It becomes automatic movement in a short time.

Few years ago, I had colleagues who came from a certain foreign country and were not used to manual transmission. They got a company car with manual transmission. The clutch was burned in one month.

[JetSetWilly]

I don't think having the clutch down destroys the clutch, how would it do that? It is having the clutch partially engaged for a very long time that would destroy the clutch.

A clutch is destroyed by friction - slippage between the two plates that comprise it. This is a useful characteristic when pausing on a hill for a few seconds but I suppose there must be some people that keep the clutch partially engaged for a very long time.

But if you are sitting at a junction with the clutch entirely depressed for a long time the plates are disengaged and no damage is done. That's a bad habit for other reasons, such as if you get rear ended your car is still in gear and could then cause a further accident.

[Reason077]

That's right. Driving with the clutch partially engaged will wear it out. But having it fully engaged while the vehicle is stopped won't do any harm.

[jpindar]

It will wear out the throwout bearing.

[flyinghamster]

Holding down the clutch pedal when stopped won't harm the clutch, but it may put excess wear on the throwout bearing that allows it to slide back and forth.

[dogma1138]

I want to see the people who cycle the clutch twice at a red signal.

[Ntrails]

When stopped you have two options in a car, sitting with your foot on the clutch (which is flat out bad) and putting the car in neutral.

Putting the car in neutral is basically one meaningful action - changing gear, yes you have to depress the clutch move the gearstick to neutral and then let the clutch go - but to describe that as "cycle the clutch twice" is madness. Am I missing something?

[Dylan16807]

You have to take it back out of neutral, making two cycles of the clutch.

No madness involved.

[mnw21cam]

Most people in the UK? At least, if they want to pass their driving test.

[apetrovic]

If I'm expecting to stop more than few seconds, I put my car in neutral. Every time. For last, let's see, 28 years since I have my driving license.

[usrusr]

What else is there to do? I don't text in the driver's seat, putting the gear in neutral gives my limbs something to do.

(It happens to involve the clutch, but that is "automatic", as in "muscle memory", even though I drive less than once a month)

[jperras]

Hi. I do this all the time if I'm going to be stopped for more than 2-3 seconds.

[rascul]

You can often take it out of gear without the clutch.

[kifki]

Manual car with start&stop owner here; I always use it when driving in the city, so do all of my friends. It's just slightly uncomfortable the first times, when you have to train your muscle memory.

[beefield]

> Stop/start reduces fuel consumption on test cycles like NEDC

I would like to know:

1. How long you need to idle to recharge the electricity to battery you use to restart the engine?

2. Does NEDC and others require that the battery has same state of charge at the end of the cycle as when beginning?

[Reason077]

Not really an issue. The energy used to restart the engine is small compared to the fuel savings. An electric starter motor is very efficient compared to a combustion engine at idle.

Stop/start will automatically disable if the battery has a low state of charge.

[aluhut]

Just have to hold your food on the brake?

It's a pain...and depending on the break, it really may become pain.

Usually if I drive my manual private car, I disengage the gear already on the way to the red light. It just rolls. I break, motor turns off. When I want to start, I push the clutch, motor turns on, off you go.

The good thing is, If I want the motor to launch, I can by pushing the clutch slightly. I can also release it and put my legs wherever I want. I can relax.

Holding one leg constantly on the break is just annoying. For you, your leg and the guy behind you who has to look into that bright red light pointlessly shining in his eyes.

[Reason077]

Just have to hold your food on the brake?

It's a pain...and depending on the break, it really may become pain.

Oh, with an automatic you have the option of putting it in Park also. Certainly, it's a good idea to do that if you're stopped for more than a few seconds. You don't have to keep your foot on the brake, but doing so is enough to activate stop/start.

[rlpb]

> You have to engage the clutch, put the shifter in neutral, and release the clutch again.

That's both a long-winded and incorrect way of putting it. If you are stopped, then you're either already in neutral with the clutch released or the clutch is already engaged. There is no other way.

Really, the rule is just "you have to have the clutch released". For experienced drivers of manual transmissions, this is one smooth action.