Replace the brake fluid or not.
Discussion
Took the Cerb to Cadwell last year and was planning on going again this year hopefully. Just wondered if would be wise to change the brake fluid as I brake fade on the last session of the day, the brakes have seemed fine since but would you say I should replace the brake fluid or should I be okay?
Thanks
Chris
Thanks
Chris
When I read threads like this I worry, a LOT. Firstly that you are asking the question and secondly that you have waited a year.
Brakes "fade" for a number of reasons but all are as a result of heat build up. What were the symptoms of your brake fade, Reduced stopping power (mechinical fade) or longer pedeal travel (hydraulic fade). Usually if the fluid is contaminated with water (which I can promise you it is to a greater or lesser degree) then you will usually get a long pedal on the first or secocnd session of the day when the water in the fluid boils. Changing brake fluid is a service item and should be done on a regular basis , especially if you are doing track days. I would say that it is essential before EVERY track day, too late if you find out after the crash.
The most likely cause in your case is mechanical fade where the repeated heat cycles without sufficient time for cooling build the temperature in the brake pads beyond the point they will operate properly and the friction between the disc and pad is lost. Everyone has different driving styles and therefore different demands on the brakes.
As an absolute bare minimum you should change the brake fluid for new and possibly invest in some temperature sensors which will tell you what brake temps you are generating so you can fit appropriate pads for your track day requirements. These MUST be changed back for road use. Continuing to use pads which get too hot can result at best in warped discs (very expensive on a Cerbera) and at worst, well you dont need me to tell you.
You are driving a 180 mph car and getting it wrong at certain points at Cadwell can put you in some very unforgiving places and remember you are not on the circuit alone, you will win no friends by damaging someone else or their car.
CHANGE THE FLUID AND INVESTIGATE YOUR BRAKE TEMPS !!!!
ps, Campbell,I would love to know how you change the fluid in the calipers.
If in doubt discuss it with someone who knows, some of the advice on these forums varies from amusing to dangerous.
Brakes "fade" for a number of reasons but all are as a result of heat build up. What were the symptoms of your brake fade, Reduced stopping power (mechinical fade) or longer pedeal travel (hydraulic fade). Usually if the fluid is contaminated with water (which I can promise you it is to a greater or lesser degree) then you will usually get a long pedal on the first or secocnd session of the day when the water in the fluid boils. Changing brake fluid is a service item and should be done on a regular basis , especially if you are doing track days. I would say that it is essential before EVERY track day, too late if you find out after the crash.
The most likely cause in your case is mechanical fade where the repeated heat cycles without sufficient time for cooling build the temperature in the brake pads beyond the point they will operate properly and the friction between the disc and pad is lost. Everyone has different driving styles and therefore different demands on the brakes.
As an absolute bare minimum you should change the brake fluid for new and possibly invest in some temperature sensors which will tell you what brake temps you are generating so you can fit appropriate pads for your track day requirements. These MUST be changed back for road use. Continuing to use pads which get too hot can result at best in warped discs (very expensive on a Cerbera) and at worst, well you dont need me to tell you.
You are driving a 180 mph car and getting it wrong at certain points at Cadwell can put you in some very unforgiving places and remember you are not on the circuit alone, you will win no friends by damaging someone else or their car.
CHANGE THE FLUID AND INVESTIGATE YOUR BRAKE TEMPS !!!!
ps, Campbell,I would love to know how you change the fluid in the calipers.
If in doubt discuss it with someone who knows, some of the advice on these forums varies from amusing to dangerous.
Go on the temperature rating of the fluid not the DOT rating, all the good stuff is DOT 4 you will find.
You want to be around 300C race fluid.
I recently (last week at Donnington) had brake problems, tracked down to a bulgy rear hose causing a long brake pedal, i used a infra red temp gauge to measure temps, the front caliper was at 265C and the rears 195C, some of the lesser fluid will boil at those front caliper temps.
I sell this stuff here (325C), but whatever you get make sure you go on TEMP spec.
http://www.clbraking.co.uk/
You want to be around 300C race fluid.
I recently (last week at Donnington) had brake problems, tracked down to a bulgy rear hose causing a long brake pedal, i used a infra red temp gauge to measure temps, the front caliper was at 265C and the rears 195C, some of the lesser fluid will boil at those front caliper temps.
I sell this stuff here (325C), but whatever you get make sure you go on TEMP spec.
http://www.clbraking.co.uk/
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