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All,

Why don't we have disc brakes even in sedans ? Are they very expensive ?

Honda City Vtec ( Old - dolphin shaped) had rear disc brakes, honda cleverly removed this feature in new city, nobody noticed :-)

Skoda Octavia - we pays 12+ lacs and we get rear drum brakes ( Petrol models got discs...thank god)

Fiesta,Linea,Ikon,SX4,City,Accent,Optra,Aveo...non e got rear discs brakes.
None of the entry level SUVs got disc, Scorpio,Safari,Innova,Tavera and to my utter surprise Ford endeavor also fitter with rear drum brakes...

Verna Petrol XXi got disc rear disc brakes and the owners do appreciate the breaking of this car.

None of Hatch backs got disc in the rear, the list includes 'Premium' hatches like Fabia,Fusion and i20.

Why is it so ? All want to improve 0-60 figure ? Nobody interested in 60-0 figure ?

Your thoughts guys...

Raneesh

good point. unless i'm missing something, indians aren't interested in safety features. again i'm not sure if this is the trend in the foreign models of the same cars.

Due to weight transfer, its logical to find discs in front. If they are present in the rear, its excellent. They do reduce the braking distance. But for premium hatches they are not required as the engines they come along are not capable of pushing them hard at high speeds.

The real need is for sedans and heavy vehicles. They need better brakes.

But IMHO, rather than asking for rear discs, we must first ask for ABS and then rear discs.

You would change your opinion after knowing what some hatches are capable of. Eg. the Getz-D.

While I don't have any idea about the cost of disc brakes, I would think that if manufacturers are not providing it for the rear wheels, it would be simply because of cost reasons (they cost more than drum brakes).

The Optra Magnum Diesel does have rear discs. The basic reason is cost cutting. Rear discs are more expensive than rear drums and hence the lack of rear discs in most C segment cars.

for 9.0 Lacs, i think CEDIA is the only the car has disc brakes in both and rear. That's why braking is excellent in CEDIA. of course, it has ABS and EBD also.

FYI, verna has only front disc barkes in all versions.

Lets also be clear that having rear discs DOES NOT NECESSARILY MEAN the car has better braking

good braking is not just about having discs all around and there are cars like OHC which provide amazing braking even with the disc drum set up ..

while at that - there are was a fairly longish thread on the "poor" braking performance of the NHC VTEC - with some people reporting skidding while braking from even 60-70kmph...

So rear discs is not = excellent braking

Providing rear disc brakes is still a purely cost based feature. Its one of the options they use to differentiate between low end and high end trims. And its not just in India. Even the Honda Civic in the US has rear drum brakes for the LX and DX trim levels, while the EX with the same engine has discs. Same for the Corolla. Of course, its a necessity in powerful cars.

if rear disc not = excellent braking means what is the purpose of having disc brakes on rear?

I have mentioned ABS + EBD + rear disc = excellent braking.

@VMG,
Verna Petrol XXi do have disc brakes in rear. My friend owns one.

Diesel and low other trims in Petrol doesn't have this feature.

RV

Rear discs do not directly translate to better braking. In certain situations it could be even be detrimental.

Most of the cars are front heavy. On hard braking more weight transfers to the front. In this case discs can be helpful to provide more braking power and better heat dissipation.

On the other hand, there is less weight at the rear on hard braking and hence less grip at the tyres. In this case rear discs may not be helpful and might even cause the rear to slide.

As mentioned above, it is not just having disc brakes. If you have disc brakes + ABS + EBD then they provide a superior braking performance. Especially when you need to brake in emergencies or on gravel/snow. In these situations your front wheels could very well be locked up and skidding and then its the rear brakes that you depend on.

ABS+EBD+ REAR DRUMS + FRONT DISCS can also provide excellent braking..

the point is to isolate that specific value add that REAR DISCS incrementatlly bring to a typical car sold in India - and I fail to see why we really need it

The main reason is that considering the indisciplined behavior of traffic we end up in emergency situations more often that not. Out of the blue we get an obstacle that can prove to be dangerous.
Coupled with this is poor driving and anticipatory measures from most of the road users. This acts as catalyst for accidents.

So I think India needs rear discs. Its true that if the rear end is not heavy or loaded, there are chances of the rear stepping out, but we have ABS + EBD getting more common.
In my earlier post also I had mentioned we first need ABS and then rear discs.

I can safely say that rear discs + ABS ( with ABD ) = better braking than the standard disc + drum combo.

Agreed. There are exceptions and the Getz D is one of them. Else, I20, Fabia dont come with engines powerful enough to push them at good speeds.

:OT question: When we press the foot brake peddle, which brakes are applied front/rear/or both.
and when we engage the parking brakes?

Regards,