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-   -   Shifting to Neutral or Pressing the Clutch when Braking - Is this right? (https://www.team-bhp.com/forum/technical-stuff/13177-shifting-neutral-pressing-clutch-when-braking-right-11.html)

Small correction - even though the braking system is hydraulic, the brake booster actually works on vaccuum created in the manifold.
(Also, i may as well mention that not all power steering systems are hydraulic)

Appuchan, you clearly havent read this thread in entirety. :Frustrati

Please re-read this post : http://www.team-bhp.com/forum/226145-post32.html
And heres one more from a few weeks back saying the same thing : http://www.team-bhp.com/forum/1107950-post103.html

Absolutely correct.

Im not sure why m_upreti says his brakes didnt work at all, i think the large difference from booster/power brakes to non-power brakes provides such a contrast that he was under the impression that they werent working at all.
The pedal gets hard, and it takes a lot more force to operate the brakes.
(Also, whether they work as well as OEM non-assisted brakes is questionable... probably not).

Previous discussion here : http://www.team-bhp.com/forum/techni...-goes-off.html

Glad you brought that up srini.
In short, yes, there is a spring effect, and that is why for REAL engine braking you have contraptions like the jake-brake. (It basically opens the exhaust valves at the TDC of the compression stroke, causing a vaccum on the "power" stroke, hence retardation both ways!)
See: http://www.team-bhp.com/forum/techni...rakes-why.html

We have discussed this "air spring" in this thread : http://www.team-bhp.com/forum/techni...tml#post901577
(Post 75 onwards)

Not really anup, once the "air spring" is expanded, it takes external force to squish it. Back to the drawing board for that perpetual motion machine!! :p(http://in.you tube.com/watch?v=hl8dM2wQB4k&feature=related)

cya
R

Oh yes... see what you mean :)

But if I was coasting down a hill with the engine off (which I wouldn't be), and suddenly felt the breaks not work, assuming I had the presence of mind, I'd put the car in gear.

Thad, it is inconceivable that you'd ever be coasting downhill with the engine turned off!

What is not inconceivable is that the engine might die on you, for reasons best known only to the errant engine! That's when we need to remember the braking power that even the 'dead' engine can provide!

And, if all goes well, nothing will be breaking during such braking, LOL! :)

Hi,

After this incident I did another experiment with the car safely parked in my premises, with the engine switched off & gears in neutral, I braked initially I could pump the brakes, they gradually got harder and after a point the same issue which I faced downhill, the brakes would not budge.

I am not a big guy (only tall), so to see if strength was the matter I called one of my friends who is a amature body builder & spends at least 3 hrs in the gym daily to try push the pedal, he also tried but to no avail, the pedle was just jammed in the top most position.

Then I started the engine & magic, brakes working as normal.

The brakes in the car were OEM, the car had run only 15000 kms, and was being serviced at A.S.S. at the required intervals, where I made sure that the brakes wre being adjusted properly.

:eek::eek:

but that's is a sign to be cautioned ! brakes are supposed to be independent of power assistance (powerassist is just to make it more effective and easier for the driver that's it).

Agree the feather touch feel wouldn't be there. but it should work !

(side Q - does Indica have power assisted brakes ?)

Hi Xeno,

Yes. All indicas and cousins do come with them.

That's what I had thought before I ventured in the scary experiment.

Let me try the same thing with my Scorpio (safely parked in my building, with ignition off) and update on the results.

You could loose control of the car in neutral at such a high speed!

Unless one is doing less than 30 kph, it is not advisable!

Sir, how does it affect the balance of the car?

Sir, keeping the clutch pedal pressed while in gear and stationary at traffic light is detrimental to the vehicle.


Thats very easy when you understand and appreciate the aftermath of some crazy accidents and how and why they happened! :Shockked:

Umm no, that makes no sense. Why would you lose control?

You can hold the clutch down with your car in gear indefinitely with NO wear. Only partial "clutch riding" leads to wear.

Guys - there is a LOT of good info in this thread - particularly posts 55 through page 8. However there is also a ton of nonsense.

Here are a few points:

*Braking is your BRAKE's sole purpose and duty. Your transmission is a transmission, NOT a brake. If your brakes are so bad that you need to use the transmission to brake - get a better car.

* Simply coasting in neutral when driving straigh ahead is NOT bad. You wont magically lose control. I can't forsee any reason to do this though.

* When engine braking - be careful! In a RWD car the engine's negative power load can lead to lift-off oversteer. Typically this is an issue only on large displacement sports cars with high inertia.

* In India it seems to make sense to be in gear all the time because you
never know what's going to happen.

* Never change gears while braking AND cornering. With so many things happening you stand a good chance of losing control. Always go into gear and de-clutch BEFORE you enter a corner.

* Always keep an eye on your rear view mirror to confirm that the person behind you isnt going to hit you if you start braking. Do this well before you brake and do this often! I have avoided at least 1 accident by watching for careless drivers this way (distractions like food, cell phone, news paper, changing diapers etc :Frustrati)

*ALWAYS be aware of who is around you and constantly plan "escape strategies" when driving. This is a great way to be accident free, because you have your exit routes planned just in case. Of course this means that you should never be "boxed in" where you cant get out.

I think thats about it for now...flame suit on! :D

During my recent highway trip, I attempted to overtake a van, with no oncoming vehicle, on an undivided road at around 100 kmph. The van driver never budged to my indications to overtake and kept accelerating. Since there were no vehicles at opposite direction, I kept moving forward until there was a bumpy road surface on the right hand side of the road.

I realized that my left foot pressed the clutch when the car was riding through the bumpy surface. I could recollect on a similar situation too (5-6 months back), I did the same thing.

Any harm in doing that?

If yes, I need to kick out that habit

PS: I rarely do that, may be once in a year
ps-1: Might be when the situation gets risky

I think it should not harm the vehicle as you said. I have many people follow this. Other please shed more light on this practice

Why would you clutch just because you were driving over bumps?
If you are accelerating and partial-clutching, I can see it wearing on your clutch a bit. I don't think you did anything "wrong". Can someone clarify?

Surprise, you need to kick that habit. It's like coasting in neutral. You have far less control while in this mode.
And you certainly not be half-clutching!

Well, welcome to Tbhp! The chances of losing control at higher speeds without any "engine drive" is definitely way higher than the other way around!

With regard to the clutch wear - atleast the old school recommends one not to keep the clutch depressed and gear engaged while stationery at traffic lights et all.

Vikram, how one will lose control by depressing hte clutch at higher speeds. I knew thats not advisable and that the precise reason why I had raised here, but wanted to know the real impact so that I get out of that quickly :)