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-   -   The best way to use the clutch, gear and brakes (https://www.team-bhp.com/forum/technical-stuff/1708-best-way-use-clutch-gear-brakes-5.html)

Hi Mithun -

I guess no point in going back to the debate. Just a few points-

#) Does down-shifting (or engine braking as we have used) quickly reduce the stopping distance?
Yes

#) Is it harmful for fuel economy / engine wear?
Yes

#) Does slamming brakes very hard help?
Not actually (unless you have ABS) - you should slam and release and slam and release to get maximum effect. This is complicated - I mean its not like full slam and full release. Approximately it goes like 80% brake, gradual 10% release, 90% brake - 10% gradual release - 100% brake - 5% release - 100% brake to stop.

#) Can we actually do it when we are facing a potential accident?
No - its very damn difficult

#) Can we do down-shifting while facing a potential accident?
Yes - I have done that and saved one lady at the cost of my tail light

#) Should you do it in normal circumstances?
No

#) What method gives the best stopping distance?
Best = Down-shifting,
Better method = Brake-release-brake release, ABS
OK method = Full-on slam (no ABS)- with brakes in good condition and decent speed
Bad method = full on slam without ABS and worn out brakes!


I guess this should address your query.
Also there is plenty of stuff in one other thread as well - so have a look around. Feel free to pm if required.

RD

No it means, you slam the brakes only. You dis-engage clutch and downshift when you reach stalling speeds. You can also use engine braking to stabilize the vehicle, if it is not eqipped with ABS.

Cheers,

Rajan

Hi,
The traffic here in Noida can get really bad, almost daily. The traffic light at some points means that I have to crawl for almost .5 to 1 km on 1st or 2nd gear.

My Swift LDI has a descent slow speed by just leaving the clutch in a gear and not pressing accelerator at all. So, during the crawling traffic time, when I have to crawl every few seconds bumper to bumper, is it OK if I just leave my clutch a bit, without pressing accelerator at all to move forward?

Infact, if i leave the clutch completely without pressing the accelerator, the speed is too fast for a bumper to bumper crawl, so i just slightly leave the clutch to inch forward.

I use a slightly different method.
Rather than using the speed of the vehicle as a guide for changing gears I use the revs as a guide.
I try to keep it between 2000 - 3500 (or the "green range" in whichever vehicle you are in) on regular driving, and it applies to all gear changes from 1st to 5th uniformly. [ I mean I shift when the revs cross 3500] This was a useful tip passed on to me by my driving instructor. I think most of the newer vehicles have a tachometer.
Of course this doesn't apply in spirited driving. :D.

How do you guys negotiate humps with brakes/clutch operation?

This is what I do:
1. Slow down (braking or downshift) and move to 2nd gear
2. Just before climbing the hump, engage clutch.
3. If I need some more momentum, release the clutch little bit (with some accelerator if need be) and engage it again. This happens rarely.
4. When the rear wheels have passed the hump, release the clutch slowly.

Am I doing the right thing?

I do exactly this on speadbreakers and everyday I encounter some 100+ speadbreakers on my way to office and back. It has worked perfectly so far both breaks and clutch are still strong after 50K kms of running Swift Diesel.

That's exactly what I do as well. I find that travelling over the hump in gear makes the ride uncomfortable.

The Tacho of Indigo XL Grand DiCOR shows Redline between 5K-6K.

What should be the Max RPM after I downshift from a higher gear to lower gear to avoid the damage to ECG (Engine, Clutch and Gearbox)?

I want to shift from 5th to 4th. What should be the Max RPM shown by the Tacho after shifting?
Same for 4th to 3rd, 3rd to 2nd, and 2nd to 1st?

Suppose after downshifting, the Tacho shows 2500- 3000rpm, does it affect the ECG in any way?

I want to avoid pressing brake pedal whenever possible.

Please help.

I used to 'Clutch-Ride' when I first learned how to drive. According to the mechanic that was the reason behind him seeing the worst clutch plates ever in his 25 year career.
I still wonder if 3.5k is the correct RPM level to shift up in my new swift or not.

Hello All,
I have some novice questions (new to manual shift driving). I have read quite a few threads/post regarding proper clutch usage and came across many posts indicating clutch should only be used for gear changes. Is this true all the time?

1. What about stop-and-go/crawling traffic situations. Some times , I am having to press and hold the clutch in these situations (either in 1st gear/2nd gear). Should i be doing this or no? I haven't tried to release the clutch in such situtions (unless i see sufficient space in front of me) for the fear of stalling the car. What is the proper way to drive in these situations.

2. What is the recommended cluth/gear usage for crossing a busy 4 laned road to take a u-turn , from left most lane (my starting point) to the u-turn . I sometimes do first gear (when there is heavy traffic) and do second gear (when there is moderate traffic and enough space for me to move little bit freely) . Of course i use indicators and watch all mirrors. In either case (first or second gear) i am holding the clutch again until i complete the u-turn. Is this right or wrong?

3. My car is a fiesta diesel (1.4 sxi) and usually i am up-shifting around 1800-2000 rpm (i usually up-shift the moment i hear little bit growling kind of sound from engine or a tad earlier) . Is this the right band for up-shift. Can any fiesta owners please enlighten me.

Thanks in advance.
sr912m.

a) Instead of crawling by pressing the Clutch in 2nd gear, drive the car in 1st gear using clutch and brake (don't use accelerator in stop-go-traffic).
b) Also don't keep pressing the clutch for more than 5-10sec. Instead shift to Neutral and remove the foot from clutch pedal.
You will save--
i) the brake in case (a) since you will have to use less brakes to reduce the speed as you don't give more accelerator.
ii)the clutch in both cases since you are not using clutch for prolong duration.
iii)the fuel since you are using the accelerator and clutch less.
Please don't drive using clutch in 2nd gear. Drive in 1st gear until you complete the U-Turn and then shift to 2nd for the reasons mentioned above.
Unless the car is fully loaded with passengers and/or luggage, it is fine to shift at the rpm you mentioned. When fully loaded, Shift at 2500-3000rpm except in 1st (you can shift from 1st to 2nd at 1800-2000rpm since 2nd will handle it without complaining).

Thanks IndigoXLGrandDI. I will follow your suggestions (except may be using neutral as that would mean more shifts)

Finally Its up to you either to shift to neutral and save your clutch or otherwise.
Just my two cents.

My question posted on 12th June 2011 is unanswered till date.
Experts Please guide me.

Since yours is a Diesel and you will be getting the turbo activated around 2000 rpm it would be better you downshift once the rpm goes below 1500. Don't be too low i.e. 1000 rpm since the car may stall.

If your downshifting from 5th to 4th gear the rpm must NOT cross 3500rpm preferably 3000 rpm. If you downshift below 1500 rpm there would be no problem.

If you use the engine braking method there is no problem on the ECG, unless your downshifting and the rpm after the shift crosses 3500rpm. Brake pedal is not needed unless an emergency and release the clutch slowly when you downshift to avoid any jerk.
Yes this is true for the most of the time. If you clutch ride then be prepared to change your clutch every 3000-4000kms.

1. NO! When in a stop-go traffic use the clutch only when you intend to move ahead and the rest times shift to neutral and release the clutch. That's a better practice than resting your foot on the clutch and keeping it depressed.

2. When taking a U-Turn please use the 1st gear as you have the needed power to negotiate the turn and since the turns are not done at more than 10-20km/hr first gear is adequate. In case your in 2nd gear the car would plunge forward fast ahead.

3. Shifting up around 2000 rpm is the best time since the turbo is getting active and the gear shifts will be smooth and fast. lower than that will get you the turbo lag and higher than that will make you loose FE since your revving the engine harder.

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