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Old 25th November 2020, 10:05   #1
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Importance of 4 disc brakes and Autonomous Brake Assist

Hi All,
One of my biggest grief when it comes to Indian Car manufacturers is how every single one of them try to skimp on important safety features and provide more gizmos and toys instead.

The feature which i want to highlight is Rear Discs. Whole buying our sedan, one of the main 3 reasons other than power, handling was braking which led me to drop the Rapid and pick up the Linea T-Jet. The Vento was dropped immediately after TD because of the pathetic brakes. The Rapid though sharper than the Vento simply couldn't inspire the confidence of a 4 Disc setup found on the Linea. Interestingly both the Rapid and Polo were being sold in the UK with similar engines along with rear discs.

Time and again I have thanked myself for the decision of picking the T-Jet since with all the morons we get to encounter on the road there are many situations where very less can be done from the driver's perspective other than hitting the brakes and praying to God!

Please have a look at my Tweet to check it out:

https://twitter.com/Nemesis06506684/...497937410?s=08

I have always seen 0-100 figures being hyped about but very rarely have I seen 100-0 or braking test figures like braking distance, time etc being highlighted. A quick car also needs to stop quickly and surely.

This is another stark Indian mentality which has come across to me since on most of the acceleration test videos I see on YouTube from EU, I have seen them quote both 0-100 and 100-0 data.

The second feature which comes really handy in such situations is autonomous brake assist or whatever they call it, basically the radar driven brake assist which applies the brakes automatically to avert a collision. Due to multiple factors a driver could have missed the car which jumped out of the bus lane, ranging from bad headlights to heavy rain fall. Its also just not limited to cars since Indians love crossing the road recklessly and we always have to watch out for people jumping out of the median on to the fast lane.

Cars like the Baleno and Ignis in the UK have Radar assisted braking while they were one of the many omissions that Maruti indulged in while launching the cars in India.

Don't you guys think both manufacturers and the customers start looking at such safety aspects more critically than going hyper over sunroofs, touchscreens etc?

I would happily buy a car with a generic audio system with Bluetooth, without sunroof and rather have such safety features along with a rear independent suspension if the makers are generous enough to throw one in.

Last edited by Aditya : 27th November 2020 at 22:43. Reason: Spelling errors
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Old 25th November 2020, 10:14   #2
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re: Importance of 4 disc brakes and Autonomous Brake Assist

Quote:
Originally Posted by adneo View Post

Dont you guys think both manufacturers and the customers start looking at such safety aspects more critically than going hyper over sunroofs, touchscreens etc?

I would happily buy a car with a generic audio system with Bluetooth, without sunroof and rather have such safety features along with a rear independent suspension if the makers are generous enough to throw one in.
Second you on this viewpoint. I am yet to understand the unmitigated obsession with features which appear completely useless to me - e.g. tiny sunroofs, mobile phone assisted ignition of car, huge entertainment systems, air purifiers, mood lighting, seat massagers and what not, and the utter disregard of many manufacturers to much more critical mechanical and safety related improvements to the cars that they manufacturing. This is helped in no small measure by customer demand, since at the end of the day, manufacturers seek to make profit and do that by giving perceived value to customers in the form of endless features and gizmos. The more "features" you have, the more proud you can be of your car, mechanical competence be damned.

While I have no issues with gizmos, and understand their relevance and even desirability for the target audience, they certainly cannot come at the cost of mechanical purity and competence of the car in question - whether it be active and passive safety features, braking, engine performance, ride and handling, seating and driving ergonomics, long term reliability and ability to perform flawlessly in demanding Indian conditions. The novelty of a sunroof wears off in no time, while the above mechanical strengths will remain critical throughout the life of the vehicle and its ownership.

Last edited by arindambasu13 : 25th November 2020 at 10:17.
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Old 25th November 2020, 10:27   #3
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re: Importance of 4 disc brakes and Autonomous Brake Assist

Honestly, 90% of your braking is done by the front brakes. I’m not saying rear brakes are useless, but they are mostly nice to have in most mass-market cars.

Regarding the driving assist, I think these systems are not exactly designed for the erratic traffic conditions in India. Companies like Jeep are having problems with the driver assist systems in the USA.
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Old 25th November 2020, 10:50   #4
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re: Importance of 4 disc brakes and Autonomous Brake Assist

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Originally Posted by landcruiser123 View Post
Honestly, 90% of your braking is done by the front brakes. I’m not saying rear brakes are useless, but they are mostly nice to have in most mass-market cars.
Picture it this way - irrespective of whether the rear has drum or disc, the front has to have certain % more stopping power than the rear - inorder to maintain correct brake bias for the weight transfer. So, if instead of rear drums, if rear discs (big enough to surpass the braking force from the earlier drums) are put => that will automatically mean the front has to get proportionally stronger, inorder to maintain the same bias. This is the real reason, why rear discs are generally sought after - the gain is not just from the drum -> disc change in its entirety, but a lions share of the increased stopping power comes from the bigger front discs.
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Old 25th November 2020, 10:57   #5
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re: Importance of 4 disc brakes and Autonomous Brake Assist

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Originally Posted by adneo View Post
The second feature which comes really handy in such situations is autonomous brake assist or whatever they call it, basically the radar driven brake assist which applies the brakes automatically to avert a collision.
Call me whatever, the first thing I do is to switch off this assistance on the Merc. It's programmed for countries where people know the difference between roads and their backyards, not for us, at least in the current day. The moment it sees a human being coming on a road, it brakes as if it's the end of the world.
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Old 25th November 2020, 11:06   #6
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re: Importance of 4 disc brakes and Autonomous Brake Assist

Quote:
Originally Posted by adneo View Post
Hi All,
One of my biggest grief when it comes to Indian Car manufacturers is how every single one of them try to skimp on important safety features and provide more gizmos and toys instead. I would happily buy a car with a generic audio system with Bluetooth, without sunroof and rather have such safety features along with a rear independent suspension if the makers are generous enough to throw one in.
Totally agree! There should be a variant that's feature loaded on safety front and less on gizmos besides the trend of top variant which has it all. Buyers who lay emphasis on safety should get such buying option. Now what's prevailing is you opt an X thing you'll be stripped off a Y and so on. Diesel comes with 4 discs but petrol doesn't get that. You opt for diesel automatic but you won't get ESC. The list goes on endlessly.

Quote:
Originally Posted by arindambasu13 View Post
what not, and the utter disregard of many manufacturers to much more critical mechanical and safety related improvements to the cars that they manufacturing.
Yes true. Further to my point above, ESC is one important safety feature which most Indian manufacturers keep skipping. I've read somewhere ESC would be mandatory come 2023.

Last edited by Bibendum90949 : 25th November 2020 at 11:07.
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Old 25th November 2020, 11:09   #7
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re: Importance of 4 disc brakes and Autonomous Brake Assist

I am with OP when it comes to better braking power in the cars.

On the flip side, I always have this fear if the car in front has excellent brakes only to get rear ended since a considerable percentage of cars on road have average brakes at best. Remember the last generation swift with brakes designed to give you thrills of your lifetime.
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Old 25th November 2020, 11:10   #8
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re: Importance of 4 disc brakes and Autonomous Brake Assist

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Originally Posted by Turbanator View Post
Call me whatever, the first thing I do is to switch off this assistance on the Merc. It's programmed for countries where people know the difference between roads and their backyards, not for us, at least in the current day. The moment it sees a human being coming on a road, it brakes as if it's the end of the world.
Wholly agree. With our cattle/humans crossing our city roads/highways at unsafe distances (from a Western PoV), what could have been a calculated light braking + swerve can instead become a emergency braking triggered by these advanced systems.

This can lead to a much more dangerous rear-ending & chain collision scenario.
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Old 25th November 2020, 11:24   #9
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re: Importance of 4 disc brakes and Autonomous Brake Assist

After driving almost 87,700 kms with disc+drum combination in the Creta, recently got a chance to drive the 2020 Creta Diesel SX(O) equipped with discs all around.

The difference that I could notice was day and night. I was in love how the car responded to brake pedal inputs and also tried emergency braking couple times from 60kmph, 80kmph and 100kmph. The 2020 Creta just stopped with least drama!

I wish Hyundai had given discs all round from Day 1 of Hyundai Creta in India.
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Old 25th November 2020, 12:11   #10
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re: Importance of 4 disc brakes and Autonomous Brake Assist

When I had test drove the Seltos with my brother there was a big bite difference between the base Petrol & Diesel. Now this difference could be because of the rear setup or the fact that the 1.5 NA does not come with a booster.

Whatever it is the Diesel came on top.
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Old 25th November 2020, 12:24   #11
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re: Importance of 4 disc brakes and Autonomous Brake Assist

My car has discs on all 4 wheels and I love the braking. It has a Bosch braking system and is very good considering its model year and a light tap on the pedal slows the car down gradually from highway speeds. No fuss, no drama. So any car that doesn't have discs all around is automatically disqualified. I don't give a hoot for those stupid gimmicks car manufacturers add to attract customers. I assign safety priority #1.

The biggest advantage of disc brakes is one can monitor and comparitively easily replace the brake pads without having to take off the drum using a puller.
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Old 25th November 2020, 14:04   #12
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re: Importance of 4 disc brakes and Autonomous Brake Assist

SPOT on Adneo.

The manufacturers and the customers to be called sinful on this drama of features and gizmos.

Coming to rear discs, its very well needed for the sporty engines being offered now a days. But no manufacturer sees them as need as does with sun roof. Many friends asks about sun roof but not 6 air bags or rear disc brakes.

Few years back ABS and air bags were offered only on top end variants. Now they are standard. Probably we will need more time / govt push for the 6 air bags and rear disk brakes to be available all across.

When I was in search for a diesel car of above 4 mtrs with 6 air bags and rear discs under 20 lacs, there were none.
Creta, City and Verna has 6 air bags and no rear disk brakes.
SCross has rear disk brakes but not 6 air bags.
Creta with rear disk brakes would have been the best bet.
Only jeep compass have it and also only on top end crossing 25L


My big WISH is to have a all safety variant with out the tech/gizmo/sunroof across cars.
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Old 25th November 2020, 15:00   #13
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re: Importance of 4 disc brakes and Autonomous Brake Assist

"I got bigger brakes than that guy's car" - said no one ever when trying to impress someone.

In the scheme of things, cars in India are a status symbol and gives one bragging rights. And guess what everyone wants to brag about - equipment, jazzy interiors and cool shades. Not four disc brakes. (exceptions being TBHP meets, for sure!)

We, as TBHP members, are a declining minority, IMO. Some people just want to make sure they showcase their worth via ostentatious displays. And cars, for one, are the perfect display of wealth. You can even take it to others homes and display your worth!

I am all for safety but ever heard of the guy who had 3 family members riding a bike and then bought a car with zero safety ratings?

Sometimes, we get over the affordability hump and then sneer at others who make choices which we have the luxury for. And while we have the best of intentions, if we put ourselves in others' shoes, we may be also forced to make some life-defining choices "Do I want a safe car or do I want something that I can pay EMI on and not get my entire family caught in the weather?" .

There's a cost to safety and some people are willing to pay it with their lives.
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Old 25th November 2020, 15:20   #14
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re: Importance of 4 disc brakes and Autonomous Brake Assist

Quote:
Originally Posted by adneo View Post
The second feature which comes really handy in such situations is autonomous brake assist or whatever they call it, basically the radar driven brake assist which applies the brakes automatically to avert a collision. Due to multiple factors a driver could have missed the car which jumped out of the bus lane, ranging from bad headlights to heavy rain fall. Its also just not limited to cars since Indians love crossing the road recklessly and we always have to watch out for people jumping out of the median on to the fast lane.
I too once wished for the same feature, when I did that, my father was sitting beside me. He immediately responded with "then people would jump in front of cars for shits and giggles, just to irritate the driver of such cars". He was right in a way. Have you not seen the people who cross the road regardless of traffic condition and just stretch out their hand in front of you as if casting a spell that'll make you stop? Not to mention the 85424 bikes that cut in with a gap of less than a couple of feets on highway speeds. I live in a city with absolutely erratic traffic and an hour's dashcam footage would be the stuff of nightmares for someone driving on EU roads.

The feature would be useful once we get our roads in order. Otherwise any time an erratic driver cuts in close, which they do so very often, your car would just keep getting rear ended. What could be done is it could be tuned for Indian conditions and EBA could at least gradually slow down you car if it detects the possibility of a collision, not brake like crazy.

We've not even considered how overtaking is done on undivided roads in India. How would such a system perform in those conditions? People cut it far too close for any autonomous system's liking.

Quote:
Originally Posted by arindambasu13 View Post
While I have no issues with gizmos, and understand their relevance and even desirability for the target audience, they certainly cannot come at the cost of mechanical purity and competence of the car in question - whether it be active and passive safety features, braking, engine performance, ride and handling, seating and driving ergonomics, long term reliability and ability to perform flawlessly in demanding Indian conditions. The novelty of a sunroof wears off in no time, while the above mechanical strengths will remain critical throughout the life of the vehicle and its ownership.
I don't want to sound snobby - that's not my intention, but a lot of money in India is recent. People who can afford cars now couldn't have even a decade ago (including my own family, fwiw). This rise in car ownership has paralleled a growth in the tech industry, the smartphone wave. This imo has led to people also seeing cars as gadgets and equipments of technology with also perform the auxiliary function of getting you from point A to B.

That can also be seen from the lack of focus on longevity of cars with people often choosing to change cars in a short span. If people cared about the mechanical finesse and competence, the kind of cars we'd see in the market would be completely different. Two of my friends recently bought a car, the first they showed me were the features of those cars. Not how it drives, what kind of engine or safety features it has, but bluetooth calling, the touch screen, sunroof, etc. One of them had the seatbelt tied from behind to circumvent the seat belt reminder.
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Old 25th November 2020, 15:42   #15
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re: Importance of 4 disc brakes and Autonomous Brake Assist

Drum brakes at the rear is not necessarily a problem at all. Lots of modern cars still have them. Certainly my wife’s Ford Fiesta has them. Not sure on the latest Ford Focus, but earlier models had them too.

Stopping power, or stopping distance if you like, is not necessarily related to having drum or disc brakes as such. Many other factors come into play.

What is true is that drum brakes are cheaper than disc brakes.

Remarkably on both my classic cars, almost 40 years and both the cheapest version of the model range, W123 200 and Alfa Spider S3, both have disc brakes all around.


As many have mentioned, braking is done primarily by your front brakes. Check out the size of the front disc and callipers and you will see they tend to be considerably larger/beefier than the ones at the rear.

Even so, you will still find brake pressure limiters on the rear brakes too. (e.g. Alfa). Just to make sure they don’t lock up prior to the front one!

I am not a fan of the autonomous brake assist at all. And that is driving around in Europe. Systems simply are incapable of distinguishing between real danger and some normal driving manoeuvring.

Jeroen
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