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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-10.html)

I would take of the legs from the accelerator and would start shifting down the gears in sequence and start braking if required to crawl over the speedbreaker & with regards to rumble strip it depends on the the height of strip. Certain places would just go over it by reducing the speed little bit else would just crawl over it & go.

Out of habit, I do a few things when I'm on a fast highway and I have to slow down for rumblers.

As soon as I spot the sign board and the actual hump/rumblers,

1. Take foot off the A, start braking. Switch on the hazards. This helps the guy behind me know that I'm braking, braking fast and shedding speed at a faster-than-usual rate for whatever reason.

2. Simultaneously along with braking, shift down 5-4-3 or sometimes from 5 to 3 directly depending on the rate of shedding speed.

3. Bring the speed down to about 30ish before about 20 - 30m from the humps, where I have a clear visibility of how big they are. If they are low-ish rumblers I can fly through, I accelerate and take them at 40 - 50 kmph. If they are big, I slow down to a crawl. All the while with the hazards on.

Most common junta understands the use of hazards being related to sharp braking. This has ensured there's no panic braking or wheel locking happening behind me and I feel is the best procedure for sharp braking on highways.

From what I understand, some cars are equipped to automatically turn on the hazards when the braking is sudden and sharp. In my car, I do it manually.

After a couple of years of driving few cars ( my experience is still limited) what I have come to understand is that keeping the car in gear and braking is the best way slow down in the least distance. Eg going from 80@5th gear to 10@1st gear, I will down shift to 60@4th- 40@3rd- 20@2nd and then finally 10@1st. This ensures that I use engine braking + brakes to slow down the car optimally. After a bit of practice or rather habit, in case of panic situations where I would stomp on the brakes and hope to stop, I now have control and stop in comparatively less distance.

Especially on a highway where there is no speed breaker marking, ensure you put your hazard lights on. The reason for this is the much higher speeds on the highway as compared to other roads. Post that if distance permits, take your foot off the accelerator pedal and let the vehicle slow down on it's own as much as possible with engine assist only. Keep lowering the gears so that ideally you are in 2nd gear before you start braking. The advantage of this is that you use engine assist to brake and scrub off speed slowly, but more pertinently, it leaves you more options in case of any eventuality. Braking is easy if need be and it is easy to accelerate if the car behind you is not slowing down. Also, if you brake late, you risk locking up your wheels.

A couple of related threads:

http://www.team-bhp.com/forum/techni...ar-brakes.html

http://www.team-bhp.com/forum/techni...ing-right.html

Cheers,
Vikram

Travelling a lot on the highways i have seen on multiple occasions that people driving ahead brake really hard to stop before a pothole, Several times a car moving in front of me has done it, What i don't understand is they don't really care whats the traffic position behind and they just brake as hard as possible, They don't realise they would do more damage to themselves and others if someone rear ends them, And yes they never use hazard lights too!

For me, If someone is tailgating me (Very common on highways) I use the hazard lights and judge accordingly the last spot for me to start braking to stop safely, Another thing i have noticed is people don't use hazard lights to warn others, But if you use it they surely do get aware and slow down.

So a suggestion, Use hazard lights if you spot a pothole, Speed breaker, Or if an accident has occurred, It mostly does help.

So you use the heel and toe method( inclusive of rev matching)? I still haven't been able to master it.
What I normally do is brake in 5th gear till the point it starts juddering a bit( that will be about 30-40 kmph) and then hit the clutch. Is that even correct? Atleast it's smooth.

Not sure if i am right but you are better off not doing that. No offence.

Car is still in top gear when you are nearing stalling speeds and you suddenly get to 1st gear post that. Engine and transmission would be cursing you during that period.

What I suggest and have been doing off-late as there are 8 strips (rumblers) that came out suddenly one night. As a habit I am at 80 kmph just before hitting the rumblers. What I do is 5-4-3-2-1 (80-60-40-20-5) downshifting with brakes pressed and if I am not able to slow down on time and have to decelerate faster I go from 5-3-2-1 (80-45-20-5) with a bit harder brake pedal input as compared to the earlier case.

If there are parts of the rumblers that are squished, I slow down from 80 to 60 kmph, align my car correctly and then fly over them without any breaking input.

EDIT:

If i downshift from 80 to 0 in the above style mentioned, revvs blip won't be too harsh (maximum would be 2500 RPM) so no need to use the toe heel method.
Clutch and brake pedal is sufficient.

Rev matching (heel toe) is the best technique. Once you master it, it will also feel smooth added bonus would be the looks and stares you get from people; some old coots will be startled, some boys will be surprised but fascinated at the same time since the blipping of revs might vaguely trigger a memory of what they saw once on youtube or the telly, and the girls I'd like to imagine feel deeply turned on :D

Jokes apart, it seriously is a huge boon when it comes to shedding speed or maintaining control of the car during high-speed maneuvers. It keeps the car more taught and quick on its feet to change direction, allows you to brake later, enter faster, be in the right gear always. Seriously, master it if you are already trying to, and you will never look back. :thumbs up

I would guess that if there were only 3 or 4 rumble strips, very few people would actually consider slowing down unless they actually knew that it was there. Mostly they would just continue to speed over it and it would be ineffective as a speed breaker. I personally try to get over rumble strips as quickly as possible if they are not too badclap:

I usually take rumblers at normal cruising speeds. The heavier the car, the better it will handle at higher speeds.

As for speed breakers, going at 100kmph and spotting a speed breaker about 100 metres ahead doesn't leave much choice. Brake, downshift simultaneously and hope no one hits you from behind and all occupants are belted up and not eating or drinking.

With family on unknown sections I tend to keep the speeds in check, so I would never be driving at sustained speeds of 100kmph in an unfamiliar territory.

I usually try heel and toe when I have company, especially elders in the back seat it it gives the best ride (not even a little jerk) while down shifting; or when I have to take a corner that I like. There are very very few corners that you can enjoy - and I don't mean taking it at 100kmph, even entering at 35-40 and accelerating out at 55-60 just after the corner is enough to satisfy me. On such corners I always heel and toe.

Braking in 5th till its juddering is a wrong technique. One reason is this - in case of a situation when you are slowing down, but suddenly need to pick up speed then you'll be caught in the wrong gear. This happens when you are slowing down at a signal in night and the moron behind is coming at speed and has no plans to stop.


On YouTube search for Senna's heel and toe. Here is the link - https://youtu.be/96ekbvjyr0g

This video shows the driver and car as one machine! The Great Senna - in a street car, pushing it to the cars limit is such a pleasure to watch.


Also, I've recently started trying left foot braking, not many opportunities, but since I'll be getting a new turbo petrol soon, I'm hoping to learn that technique as well. But that's another topic in itself.

Most importantly whatever car you drive, niceties like heel and toe, left foot braking etc will keep you entertained in the mundane everyday traffic conditions. You will start having better control, more precise cornering and have a better control on your vehicle than your peers.

This is the method I use to slow down on a highway, and my stock brakes have lasted 60,000kms+ on both my previous cars.

When I sense a rumbler approaching, and I'm in top gear, I use the brake intermittently to bring the speed down. By intermittent, I mean, I mildly apply brakes and then release, and continue this till I bring the speed down completely, while also downshifting. Better heat dissipation results in the above method and this greatly helps in the longevity of brake shoes and lining.

This is better than the other method of coasting and braking at the last minute, as the brakes have to deal with a lot of inertia leading to excessive heat and premature wear.

Of course, these are ideal situations. When a 2 legged fool darts across the highway, there's nothing else to do but slam the brakes. Also, if there are a series of rumblers approaching at short intervals, I usually maintain a lower speed to slow down faster.

Failure to spot the speed breaker in the first place means distraction. First get those distractions away. The easier way to spot is the vehicle in front of you. If you are alone, make sure you have the slow counting 1 to 6 technique to monitor whats in front of you to react.

When its a distraction and i end up seeing a speed breaker that i need to stop, i only try to slow down and not halt. My intention is to enter the speed breaker at the slowest speed i can from the current spot. And I usually raise an alarm inside the car for passengers to be ready for a jolt and hope i can slow down in time. And when in unknown routes i usually not tend to drive at speeds that does not allow me to react. And my reference is always a vehicle in front of me in an unknown road. If i am alone i dont drive at insanity that can lead to emergency breaking situations.

Thanks all for your replies. Good to know the different perspectives on the first point about slowing down.

On my last point, i should have been clearer. The ones that i encountered on NH3 were not smooth small rumble strips (like the ones that are marked yellow), but literally a series of small sharp speed-breakers, and not just one or two, but a series of 15-20. Perhaps someone who has driven on that road (especially between Nasik-Dhule) can understand better. They definitely don't appear to be of the type on which you can just drive at high speeds. I saw all vehicles slowing to a crawl on those - and there it became tricky to choose the right gear: if you use second, there was a real danger of stalling or else riding the clutch to prevent that, and first was too jerky :eek: