[inmate]

Originally Posted by equinox22

@inmate: If that is the logic then the same should apply to the front disk brakes too right? And why would the clamps hold the expanded brakes in the first place? The brakes are not heated until they are applied. They would expand only when they are clamped onto, which would improve the braking performance.

@Limpid: The size difference for the disks is due to the fact that the braking requirement is greater for the front wheels. The same reason why some cars have disks at the front and drums behind.

I must apologise equinox , the last post was with respect to hand brakes. Hope it makes sense now. The heating happens after constant braking throughout the drive and finally contracting when parked( not in use)

[TeddyBear]

Team, We used to suffer a lot with our Amby's & Padmini's during Chennai's rainy season, when roads are clogged with water. We used control the speed and brake by lowering gear. It will take a day or two for the brakes to back to normal.

Same fate for the two wheelers, submerged till their drums.

Don't know about the moden hatches, which are using drums in rear.

[equinox22]

Originally Posted by inmate

I must apologise equinox , the last post was with respect to hand brakes. Hope it makes sense now. The heating happens after constant braking throughout the drive and finally contracting when parked( not in use)

Makes more sense now! Though it would only be an issue if you had continuous aggressive braking and then immediately stopped and put the handbrake on. That too only on a steep incline. Also if the handbrake is in the form of a drum inside the disc rotor then it would not be a problem.

[alexnazim]

Well, in India with the persistent parking problem, it is always advisable to go with drums in the rear, cause when your car gets towed, it is better to burn some shoes instead of your tyres screeching along with the crane!

[Takumi-san]

*bump*

quick question - especially for the SUV owners. Given that these are always cribbing about needing more braking; an example that comes to mind is the Scoprio (dont know about the Safari) where owners often suggest not going above a certain speed since it takes time to stop. Why wont Mahindra or Tata go in for rear discs? At least in the top 2 models ? I am sure people would really like such a feature. I have noticed that abroad even the hatchbacks and most sedans have been having all 4 disk brakes since a long time (at least more than a decade). If we clamour for air bags (which dont even inflate in instances) at least we could think of these brakes as more VFM being that they are being used every single day? I dont see how cars costing more than 10 lacs can justify not having rear disks.

Is it possible to optionally get these installed from the company? Hope someone from Mahindra / Tata is listening. Id love to see why not. Besides, these 'heavy' vehicles would be best suited especially given that users often feel the need for better brakes.

[MBG_Evo]

Originally Posted by Takumi-san

I have noticed that abroad even the hatchbacks and most sedans have been having all 4 disk brakes since a long time (at least more than a decade). If we clamour for air bags (which dont even inflate in instances) at least we could think of these brakes as more VFM being that they are being used every single day? I dont see how cars costing more than 10 lacs can justify not having rear disks.

Is it possible to optionally get these installed from the company? Hope someone from Mahindra / Tata is listening. Id love to see why not. Besides, these 'heavy' vehicles would be best suited especially given that users often feel the need for better brakes.

First - Love your Id! Initial D FTW!

Secondly - Not all modern day cars have discs. My wife's 08 Honda Civic has Cruise Control/Leather/Sunroof but no discs in the back! lol Yes somthing i noticed the min. i saw the car but didnt bother because I love the car the moment i took it for a test drive! Also, OEM replacement break discs with Pads are nearly around $300 a set (rear or front)

[GTO]

Originally Posted by MBG_Evo

My wife's 08 Honda Civic has Cruise Control/Leather/Sunroof but no discs in the back!

In Kuwait? The Indian Civic has had discs - front & back - from day one of sale. Nice to hear of an Indian variant being better equipped than our neighbours (for a change )

[Takumi-san]

shhh, GTO - honda might just hear you. Didnt they give rear discs in the OHC and removed them in the later versions? And I thought they always improved cars going forward.

[MBG_Evo]

Originally Posted by GTO

In Kuwait? The Indian Civic has had discs - front & back - from day one of sale. Nice to hear of an Indian variant being better equipped than our neighbours (for a change )

lol! yes, thats good for a change. Honda might have realized the need for better breaking in India! The way the traffic is there, driving IS AN ART!

btw, noticed that we have the same alloys that are on the indian variants, but not for the EXi.

Pics : coming soon!

[equinox22]

India seems to be ahead of all in this regard. Even the base models of the Civic in the US have rear drums.

[msaudf]

one important thing everyone is forgetting here is braking bias. by fitting rear drums the master cylinder need not be adjusted for bias as drums as we all know has less stopping power.
and i'd also like to remind you bout F= m X a, the force needed to stop the vehicle is directly proportional to the mass and the acceleration of the vehicle.
i am sure the braking performance improves by having discs all round but then its only applied to when required.
i am no expert but just that av driven and experienced both types and all drum types too.
another thing thats got me curious and thinking when relating to this subject is, Why do trucks and buses have drum brakes all round when they are heavier than our cars and jeeps? (some even go faster, the crazy volvos!!)

[equinox22]

^^ Most heavy vehicles have other ways of slowing down like retarders or exhaust brakes before the friction brakes are applied. One of the main reasons for using drums is the cost. Also many new buses and trucks are moving to disc brakes now. The Volvo B7R has disc brakes with ABS.

[msaudf]

I never knew the new Volvo B7R busses came with disc brakes, good point there equinox.
so then i guess its all down to saving money (for the manufacturers).

[dustom_99]

Originally Posted by d_himan

Are they really so expensive? From a A.S.S perspective, the Discs themselves are really cheap (~280 bucks for Swift)....

280 bucks for swift disk..?
where on earth did u find it? guess at 45 rs a kg even cast iron would be more expensive then that, let alone moly steel used in disks.
and all that cost of machining them to micron level tolerance and making the rotor drilled.hell they are expensive.
i know only the rotor of bullet cost RS 4200/ alone.
and yes they have to be dynamically balanced as well without adding corner weights and all.
so if u find a disk for RS 280 i want the dealership please!

[im_srini]

Originally Posted by d_himan

From a A.S.S perspective, the Discs themselves are really cheap (~280 bucks for Swift)....

Hi Himan, Maruti spares are cheap, but not that cheap

If I remember correct, the Alto's front disks themselves cost around Rs.600 each.

The Swift's front disks, which are ~2" wider (diameter), & are also vented, cost around Rs.1,600 each.



P.S. - All prices are 2008 April prices