News

F12 rear rotors hot

Discussion in 'FF/Lusso/F12/812S' started by italiafan, Dec 24, 2019.

  1. italiafan

    italiafan F1 World Champ

    Jul 19, 2006
    10,801
    FL and NC
    Full Name:
    Stickbones Swagglesmith
    Just got back from a drive and felt heat coming from rear wheel well so I touched both rear rotors and so hot would burn you if touching for more than 1/2 second....but front rotors ambient temp (actually cool to touch).
    Something wrong?
    Brake pad rubbing?
    Thx!
     
  2. To remove this ad click here.

  3. Solid State

    Solid State F1 Veteran
    Rossa Subscribed Owner

    Feb 4, 2014
    6,087
    Full Name:
    Nosmo King
    Likely nothing wrong. The rears get hot without the fronts when the drivers aids kick in especially in cooler weather where traction is lower. Many of the functions of the Manettino setting employ the use of the rear brakes to perform the magic of getting the massive power to the ground. I saw this after a light drive where I did not deploy brakes yet rear discs had heat like yours and fronts were cool. Switched the setting to above Race and eventually ESC Off for more of my driving. Must be careful though and have good tires with correct pressure and up to temp.
     
    Caeruleus11 and italiafan like this.
  4. mthompson2376

    mthompson2376 Karting

    Feb 2, 2017
    190
    North East England
    Full Name:
    Mark Thompson
    As thread above, in addition the rear exhaust boxes are right there in that zone and create a lot of heat in that part of the car. Pretty normal, I can always feel the heat pouring out of the rear wheels zone after a decent run on my F12. The carbon brakes can run into excess of 600 C. Definitely enough to burn anything instantly.

    My opinion from what you say is the car is running normal.

    The only thing to check but highly unlikely is that the handbrake isn’t sticking, simply drive the car slowly away say 5-10 mph, drop it into neutral (pull both levers) and feel for any drag. If the car groans from the rear and doesn’t roll freely then the handbrake will need adjusting, A draggy hand brake (on the inside of the rotor hub) would create massive heat quickly.




    Sent from my iPhone using FerrariChat.com mobile app
     
    Caeruleus11 and italiafan like this.
  5. italiafan

    italiafan F1 World Champ

    Jul 19, 2006
    10,801
    FL and NC
    Full Name:
    Stickbones Swagglesmith
    Thanks I’ll give that a try. Both rotors were equally hot though, does handbrake function on both rotors?
    I shot an email to the dealer this morning...I’ll let you folks know what they say.
     
  6. mthompson2376

    mthompson2376 Karting

    Feb 2, 2017
    190
    North East England
    Full Name:
    Mark Thompson
    Yep, brake shoes in the inside of both rear rotor housing, for some reason, one the first electrical failures because of a poor or weak battery is the Electronic Parking Brake, EPB failure and sometimes does not release the handbrake, again rare, and this would show as a failure warning light on the dash, so unless you have the dashboard warning light, definitely not that.

    again a quick charge and/or reset by disconnecting the battery (loads of threads in here on how to do that) usually cures that.




    Sent from my iPhone using FerrariChat.com mobile app
     
    Caeruleus11 likes this.
  7. To remove this ad click here.

  8. italiafan

    italiafan F1 World Champ

    Jul 19, 2006
    10,801
    FL and NC
    Full Name:
    Stickbones Swagglesmith
    I did as you suggested and popped car into neutral at about 20 mph...car rolled effortlessly arguing against brakes dragging. I’m going to take into dealer regardless and have them take a look. Probably nothing, but would hate to get some repair bill later for prematurely worn rotors.
    Thanks again.
     
    Caeruleus11 likes this.
  9. Motob

    Motob Formula 3
    Professional Ferrari Technician

    Nov 11, 2003
    2,184
    Berkeley, CA
    Full Name:
    Brian Brown
    The parking brake shoes dragging on the disc hubs would not cause the friction surfaces of the CCM brake discs to get hot (it would destroy the brake shoes and overheat the metal disc hats). What is happening is that you are driving to the point that the VDC (Vehicle Dynamics Control) is activating the rear brakes in order to keep the rear of the car in line. What Manettino setting are you using and how are you driving the car?

    I have seen a customer destroy a rear set of brake rotors in one track day when using Sport and Race mode. He was driving the car close to the limit and was letting the rear brakes control the slides coming off of the corners. The higher the Manettino setting, the less the rear brakes are used. The only Manettino setting in which the VDC is off is CST off, and even then the VDC works under braking.

    Read your owners manual about the Manettino setting, how the CST/ESC works and how to view what level each of the systems is at by viewing the Manettino parameters display while in VDA (Vehicle Dynamic Assistance) on the left TFT dash display

    Brian Brown
    San Francisco Motorsports
     
    Caeruleus11 and italiafan like this.
  10. mthompson2376

    mthompson2376 Karting

    Feb 2, 2017
    190
    North East England
    Full Name:
    Mark Thompson
    My experience of a 458 with exactly the same rear brake set up as the F12 was proof that dragging rear shoes within
    the bell housing caused huge heat, it was down to the electronic brake not releasing correctly and I need to limp home only 1/2 mile, by the time I got home, the brakes, wheels everything in that zone was super hot....from a cold start. I was sharing my experience not theory. A simple battery charge fixed the problem, the brakes released every time after that. I did get the car checked and no damage done other than some minor excessive wear of the shoes but well within limits.

    My F12 always runs hot in that zone and I do agree, a huge amount of heat can be caused through the traction control systems grabbing the brakes....so is probably not a problem.



    .


    Sent from my iPhone using FerrariChat.com mobile app
     
    Caeruleus11 and italiafan like this.
  11. italiafan

    italiafan F1 World Champ

    Jul 19, 2006
    10,801
    FL and NC
    Full Name:
    Stickbones Swagglesmith
    Thanks guys.
    I have the car in Race mode. But yesterday drove it again and also in auto mode (the horror! :)) very very conservatively, like a grandma...and rotors were once again uniformly extremely hot. Then I took out my flawlessly running 458 Spider with 34K miles on it, drove the same way...and rotors also extremely hot. I think it must be normal operation and I am overthinking this.
    Will have dealer just take a look when in next just to be double-dog sure.
    Thanks again!
     
    mthompson2376 and Caeruleus11 like this.
  12. To remove this ad click here.

  13. Gh21631

    Gh21631 F1 Veteran
    Silver Subscribed

    Feb 24, 2011
    6,148
    East
    I just watched an older Chris Harris video where he shreds on an F12 and the alert pops up about brake cooling so it must be a common result.
     
  14. Motob

    Motob Formula 3
    Professional Ferrari Technician

    Nov 11, 2003
    2,184
    Berkeley, CA
    Full Name:
    Brian Brown
    The F12 has an active brake cooling system. When the front brakes reach a certain temperature, this system is activated and two flaps on the front spoiler that are normally closed open up, providing cooling air for the front brakes. A message comes up on the dash when the system is active.
    The front brake flaps are normally closed for better aerodynamics at speed.
    It has nothing to do with the rear brakes getting hot.

    Brian Brown
    San Francisco Motorsports
     

Share This Page