AP Racing Brakes

[fa57 son]

Guys i have another thread open about the size of the master Cylinder BUT...

I need some advice..

I have a Clio 182 with AP Racing 4 POTS and from what i can tell it has KTR braided lines aswell.. BUT i seem to have alot of pedal travel.. has anyone else had this..

I have Bleed the brakes, Done a full brake fluid change, Checked for un-even wear on the pads, No leaks as Fluid has not reduced.

Anyone know what may be causing this or how to fix it..

Bigger cylinder, different lines or anything else??

Ta

 

[fa57 son]

Bump

 

[jjones82]

As you got more pistons to move in your brakes, its using more fluid to push the pistons therefore more travel in your pedal, only way to resolve this is i believe a bigger master cylinder

 

[Fred@BTM]

not neccesarily, the 4 pistons could share the same area as the stock single piston, or in some cases be smaller

 

[fa57 son]

Ok, so .. I guess i need 2 find out the volume of fluid needed to move the pistons including rears and the amount of volume the standard cylinder pushes out..... Does anyone know either of these stats??

@fred... What else could it be??

 

[mark123]

Assuming you haven't changed the rears.

Just measure the diameter of the pistons in the new calipers and the old. Then work out the total area ((pi*(diameter/2))^squared) for each setup.

If the new setup has a much larger piston area you will need more fluid to push them out.

Surely someone else must have these that you could ask? Or the company you bought them from?

 

[Fred@BTM]

is it the off the shelf AP clio kit?

what pads you running?

 

[watson182cup]

There is most likely to be still some air in the system. Just try bleeding them up again.

 

[fa57 son]

i believe it is the off the shelf kit from Daemon tweaks.. not 100% sure what pads i believe the DS-2500

@Watson: i dont believe it is this as i got my local garage who does all me work to changed the fluid

 

[JamesT87]

as Fred said, on my saxo I went from the gti6 brake setup with the 23mm m/c and went for a hi spec moster setup and the pedal travel was less, check your pads, air in the system or something maybe flexing somewhere if all that fails upgrade the m/c size.

James

 

[fa57 son]

James as far as i and the garage can tell everything else seems ok... As long as the KTR lines are ok? what peoples experiences with these .....

What M/C can i put on .. i.e megane or clio 200 or something, or do i need to take old one off and try 2 find 1 with same figment

 

[rich-6]

I was under the impression you have to bleed the inside and outside a couple of times on 4 pots to get all the air out, Bleeding just one side wont work

 

[fa57 son]

TBH i have no experience with 4Pots but i noe when i done it i bleed 1 half the the other is this how it should be done?

 

[JamesT87]

just have a check to see if the bleed nipples point up and dont face down, that was the pitfall I fell in.

Have you pressure bled them or he conventional pumping the brake pedal way?

 

[Fred@BTM]

yeah how are they bleeding them, a normal garage might not be doing it correctly

 

[fa57 son]

the bleed nipples are facing up.. im not sure how he done it, i used the conventional pump pedal whats the difference?

 

[Fred@BTM]

needs pressure bleeding IMO, pumping method is ok but it amazes me how many people f**k it up

 

[fa57 son]

ok, and do you do both nipples at same time?

 

[rich-6]

ok, and do you do both nipples at same time?

No Inside then outside IIRC

 

[fa57 son]

ah ok, im not sure if it is air in the fluid... as gets pedal does get hard when car is of..

 

[JamesT87]

get them pressure bled as Fred said you will then at least know they are bled and it must be the m/c

 

[Fred@BTM]

and just because you have 4pots don't expect a rock hard pedal, it doesn't work like that!

 

[fa57 son]

@fred yeah i do understand that but i also feel it should be a lot better than one it is