[HELP] No Grip after mod drum to disk brake

BeCool

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BeCool

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Dear all Sifu,


Good Day.
I have a problem here.
Im driving a kelisa, due to engine kong and i upgrade to 1.3cc engine. Puspakom & JPJ order me to changed drum brake to disk brake.

I have change the drum to disk brake, but the problem is there is not enough grip on it. Puspakom need the grip level at 60%. But my grip level only up to 27%

I have tried to ask quite a number of the workshop, actually they dun know how to do it

I have checked the kcar website, unfortunately we need to customize the brake system. I need to customize a valve which allowed master pump direct to the caliper and change 1 of the brake pipe

Anyone know the machinery shop or any workshop can recommend to solve my problem?
Really need you help for this issue
or else now im stuck here and puspakom will not give me the approval.

Very appreciate if anyone of Sifu can guide me the way....

Many Many Thanks!!!
:adore::adore::adore::adore::adore::adore:
 

ehdrian

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ehdrian

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maybe u can use a bigger brake servo pump..
 

Izso

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Izso

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Basically you need a master brake cylinder and proportioning valve from a car that uses rear disc brakes la. Possibly could do with just the proportioning valve only since rear drums probably use less pressure than discs.
 

BeCool

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BeCool

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Thanks for the reply =)

halfcut shop should have the master brake cylinder and proportioning valve right?
 

Dayline668

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Dayline668

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The easiest way in your situation now is to tighten the handbreak cable till break pad touching the disc then u will hav more breaking power, but that is not a solution. But it work for me.
 

^pomen_GTR^

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^pomen_GTR^

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hehehe...actually yes the handbrake grip level was down...but braking overall i think improved....

u can opt for new and better brakepads along with cross-drillled disc....that should do the trick....

even proton cars with rear disc brake (original/converted) also facing similar problem....

another is like many suggestion above install brake balance controller valve...

---------- Post added at 10:56 PM ---------- 6 hour anti-bump limit - Previous post was at 10:50 PM ----------

try using new and better brake pad alongside with sending the disc to be cross-drilled....

it is common ppl feels that their handbrake not as grip as before after changing into rear disc set....even proton cars be it original or swapped rear disc also facing similar problem....


other alternative like suggested above is to install brake distribution control valve....
 

BeCool

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BeCool

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many Thanks for all the Sifu tips.

Will try to tighten the handbrake until brake pad touch the disk first, if still failed the inspection then i will get a master brake cylinder and proportioning valve from a car has rear disk brake.

Very appreciate for all of your fast response

:adore::adore::adore:
 

VectorX2

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many Thanks for all the Sifu tips.

Will try to tighten the handbrake until brake pad touch the disk first, if still failed the inspection then i will get a master brake cylinder and proportioning valve from a car has rear disk brake.

Very appreciate for all of your fast response

:adore::adore::adore:
would suggest going for the master cylinder, don't over tighten the handbrake cable or u might jam your brakes

normal for disc brakes to be not as grippy as drum brakes, as the whole point of disc brakes is to dissipate heat faster but drum has better braking power when its cold (depending on the drum and disc compared) since puspakom inspect braking power when the brakes are almost cold, definitely the disc brake would give less grip.

would recommend getting a new servo and distribution valve, den get urself a set of brake pads which works right from room temperature, and also slotting the disc would help, cross drilling wun help u pass the inspection but it would benefit u later when u really put the rear disc brakes into use...

dunno what are the effects of the modification of putting direct brake lines from master servo pump to the rear calipers, but sounds kinda risky, too much braking power at the back without the front to balance it up on a FF car might actually cause rear wheels to lock easily, dunno if this is true for all but i experience it myself...
 

8voltpreout

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"The brake shoe carries the brake lining, which is riveted or glued to the shoe. When the brake is applied, the shoe moves and presses the lining against the inside of the drum. The friction between lining and drum provides the braking effort. Energy is dissipated as heat.

Modern cars have disc brakes all round, or discs at the front and drums at the rear. An advantage of discs is that they can dissipate heat more quickly than drums so there is less risk of overheating.

The reason for retaining drums at the rear is that a drum is more effective than a disc as a parking brake."

Brake shoe - Wikipedia, the free encyclopedia

TQ wikipedia!:biggrin:
 

zx12

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zx12

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You have to go for PG10 inspection at JPJ right?

Here's something I found out. Rear disc brake is not mandatory. My friend upgraded from 660 to 1.0 on his Kancil, and the same thing happened like you. People told him it's mandatory to have rear disc brakes, which he installed and same as you, the brakes failed the test. Even the JPJ officer who tested his car said use drum only la, just make sure it grips.

Sure enough, he swapped back to drum brakes and went in for inspection again, and this time he passed. It was at JPJ Padang Jawa.

A little off topic but it might help you to get your car endorsed. Good Luck!
 

VectorX2

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You have to go for PG10 inspection at JPJ right?

Here's something I found out. Rear disc brake is not mandatory. My friend upgraded from 660 to 1.0 on his Kancil, and the same thing happened like you. People told him it's mandatory to have rear disc brakes, which he installed and same as you, the brakes failed the test. Even the JPJ officer who tested his car said use drum only la, just make sure it grips.

Sure enough, he swapped back to drum brakes and went in for inspection again, and this time he passed. It was at JPJ Padang Jawa.

A little off topic but it might help you to get your car endorsed. Good Luck!
agreeing with you, but from his first post seems like he went to for testing with the drum brakes and failed. maybe he could try with a bigger drum brake from MPV or something.