I completely agree with Jod...
Adam if you are getting brake fade its either mechanical or you are driving way too fast....
I have only experienced brake fade on one car I have when the discs had got too thin. I changed them and it went away. Its also possible that you have the wrong or cheap pad material. If you have moprod or other 3rd rate crap pads then bin them and get some decent mintex or unipart boxed ones. These will be fine....
I hear what the guys with tuned sprints and track day use say but the std setup is perfectly fine for an 1850 or sprint road use unless you are regularly driving long downhill passes 4 up...
Blind beds in the dark...there are lots of things with no lights that could be in the way, but only some of them will kill you...
Jonners
Sierra Brake mod
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Jon Tilson
- Guest contributor
- Posts: 11179
- Joined: Tue Oct 03, 2006 9:45 pm
- Location: Middlesex
For once...
Note from Admin: sadly Jon passed away in February 2018 but his humour and wealth of knowledge will be fondly remembered by all. RIP Jonners.
The trick is to always pretend there is something to hit exactly where your line of sight ends. Driving on unmetalled roads there is no way at all you should need or even be able to apply your brakes hard enough to get fade without locking everything up. I'd be inclined to agree with Jonners that there's something mechanical at fault.
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dailysprinter
- Guest contributor
- Posts: 437
- Joined: Fri Oct 06, 2006 7:31 am
brake fade
I always managed it with perfect brakes, on long down hill without any lock ups. They are just not up to the job FULL STOP.
Brake mod only safe way to go unless you want to drive like a snail, especially as I tow a fair bit too.
Brake mod only safe way to go unless you want to drive like a snail, especially as I tow a fair bit too.
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2F45T4U
Some things to have a look at there then. Check disc thickness and fit some pads of known origin / type. If you've been fading a bit, why not bleed some more fluid through, three or four pumps per corner should move some fresher fluid closer to the heat source.pads that I got off George, MoProd maybe??? and fairly thick discs...
I've only had brake fade once,, going down a 1 in 4 hill in the Yorkshire dales in my Midget and total brake failure once, again in the MG, coming off the A42 towards Donington Park one Sunday morning, coming to the T junction at the end of the slip road, hit the anchors and absolutely nothing happened, all thanks to a broken pipe under the car. A feeling i'll never forget. Brakes are pretty simple really and kinda useful, so never ever skimp on the maintenance.[/code]
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Judge Mental
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2F45T4U
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dollysteve
From memory
Harking back to my college days, brake fade is caused by the gaseous cushion resulting from the friction material becoming overheated, this heat can also transfer through to the fluid causing it to boil.
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Lewis
Brake fade is caused by two things - When the fluid in the brake system exceeds its boiling point due to hard use, bubbles can form in the brake lines and calipers. Since these bubbles can be squeezed smaller by pressure from the brake pedal, the pedal tends to "go soft" and may even go to the floorboard without the brakes working properly.
It is also due to the reduction in stopping power caused by a buildup of heat in the braking surfaces (and in the case of drum brakes the change in dimension of components in response to heat) . It occurs most often during high performance driving or when going down a long, steep hill. Owing to their configuration this is more prevalent in drum brakes. This reduction of friction can be caused by the gasification of organic materials in the brake pad causing a gas cushion to form between the pad and disk, or by the melting of the binding resins in the pad that then act as a lubricant.
For the record, brake fade and rotor warping can be reduced through proper braking technique; When running down a long downgrade that would require braking simply select a lower gear (for automatic transmissions this may necessitate a brief application of the throttle after selecting the gear). Also, periodic, rather than continuous application of the brakes will allow them to cool between applications. Continuous light application of the brakes can be particularly destructive in both wear and adding heat to the brake system. Finally, new brakes should used as gently as possible for the first 100 miles or so to "break them in" and eliminate fade.
It is also due to the reduction in stopping power caused by a buildup of heat in the braking surfaces (and in the case of drum brakes the change in dimension of components in response to heat) . It occurs most often during high performance driving or when going down a long, steep hill. Owing to their configuration this is more prevalent in drum brakes. This reduction of friction can be caused by the gasification of organic materials in the brake pad causing a gas cushion to form between the pad and disk, or by the melting of the binding resins in the pad that then act as a lubricant.
For the record, brake fade and rotor warping can be reduced through proper braking technique; When running down a long downgrade that would require braking simply select a lower gear (for automatic transmissions this may necessitate a brief application of the throttle after selecting the gear). Also, periodic, rather than continuous application of the brakes will allow them to cool between applications. Continuous light application of the brakes can be particularly destructive in both wear and adding heat to the brake system. Finally, new brakes should used as gently as possible for the first 100 miles or so to "break them in" and eliminate fade.
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Jon Tilson
- Guest contributor
- Posts: 11179
- Joined: Tue Oct 03, 2006 9:45 pm
- Location: Middlesex
Laws of Physics...
Its down to the coefficient of friction between the pad and the disk. This is temperature related in a failrly complex way. (I cant remember the formula!) Its also dependant on the pad material, the disc material and the termal equalibrium that may or may not ne reached.
In an ideal braking world your pads and discs will reach a thermal equlibrium when braking repeatedly...that means that no matter how much more you try and stop, the brakes cant get any hotter, so the discs and pads can shed heat as quickly as they get it in from the friction stopping your car....so no fade. In practice this is NOT achieved by most production cars, because its expensive to achieve and may actually result in a braking system not suitable for road use....unresponsive brakes until warmed up. Even some so called supercars will cook their brakes at the Ring.
In the real or dolly world, the pads overheat to the extent that they stop being so grippy....the coefficient changes and they may overheat. This can reach the stage where pads disintegrate completely. I had this on a Spit with a sticking calliper! Fluid can of course boil and give a vapour lock, but this will mean a sudden very spongey brake pedal, if not loss of all braking effort. This is NOT the same as fade but may well occur simultaneously.
Its utterly pointless generating more brake force than tyres can transmit to road. All this does is give locked wheels...hence ABS.
In true Triumph engineering style a dolomite is under braked and cannot with its std setup achieve the virtuous circle described above. It is therfore possible to achieve brake fade in heavilly loaded/high speed/track situations....so drivers beware. It is No Prodrive Imprezza WRX.
But for normal road use a good set of pads and discs IS up to the job
and if you want to get it better its up to you on how your spend your money.
Jonners
In an ideal braking world your pads and discs will reach a thermal equlibrium when braking repeatedly...that means that no matter how much more you try and stop, the brakes cant get any hotter, so the discs and pads can shed heat as quickly as they get it in from the friction stopping your car....so no fade. In practice this is NOT achieved by most production cars, because its expensive to achieve and may actually result in a braking system not suitable for road use....unresponsive brakes until warmed up. Even some so called supercars will cook their brakes at the Ring.
In the real or dolly world, the pads overheat to the extent that they stop being so grippy....the coefficient changes and they may overheat. This can reach the stage where pads disintegrate completely. I had this on a Spit with a sticking calliper! Fluid can of course boil and give a vapour lock, but this will mean a sudden very spongey brake pedal, if not loss of all braking effort. This is NOT the same as fade but may well occur simultaneously.
Its utterly pointless generating more brake force than tyres can transmit to road. All this does is give locked wheels...hence ABS.
In true Triumph engineering style a dolomite is under braked and cannot with its std setup achieve the virtuous circle described above. It is therfore possible to achieve brake fade in heavilly loaded/high speed/track situations....so drivers beware. It is No Prodrive Imprezza WRX.
But for normal road use a good set of pads and discs IS up to the job
and if you want to get it better its up to you on how your spend your money.
Jonners
Note from Admin: sadly Jon passed away in February 2018 but his humour and wealth of knowledge will be fondly remembered by all. RIP Jonners.
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dollysteve
[quote]It is also due to the reduction in stopping power caused by a buildup of heat in the braking surfaces (and in the case of drum brakes the change in dimension of components in response to heat) . It occurs most often during high performance driving or when going down a long, steep hill. Owing to their configuration this is more prevalent in drum brakes. This reduction of friction can be caused by the gasification of organic materials in the brake pad causing a gas cushion to form between the pad and disk, or by the melting of the binding resins in the pad that then act as a lubricant.
For the record, brake fade and rotor warping can be reduced through proper braking technique; When running down a long downgrade that would require braking simply select a lower gear (for automatic transmissions this may necessitate a brief application of the throttle after selecting the gear)
I agree entireley with this, back in september my girlfriend and I plus a couple of friends were on the Staples 2 Naples rally, we drove 3 swiss mountain passes 1 day in an auto Subaru legacy estate, yes the brakes got hot enough that you could smell them, but not once did we get any brake fade, we used the gearbox/engine breaking and liberal use use of the brakes. I seriously doubt there are many roads in this country that are as hard on your brakes as Stelvio, La Tremola or the St Gothard Pass, even the team driving an Allegro did the passes with no breaking problems.
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For the record, brake fade and rotor warping can be reduced through proper braking technique; When running down a long downgrade that would require braking simply select a lower gear (for automatic transmissions this may necessitate a brief application of the throttle after selecting the gear)
I agree entireley with this, back in september my girlfriend and I plus a couple of friends were on the Staples 2 Naples rally, we drove 3 swiss mountain passes 1 day in an auto Subaru legacy estate, yes the brakes got hot enough that you could smell them, but not once did we get any brake fade, we used the gearbox/engine breaking and liberal use use of the brakes. I seriously doubt there are many roads in this country that are as hard on your brakes as Stelvio, La Tremola or the St Gothard Pass, even the team driving an Allegro did the passes with no breaking problems.
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Leeds Sprint
Brake Fade
Hello All
I have experienced some loss of breaking performance in my 1978 Dolomite 1850.
This occured on some very hot summer days this year with a heavily loaded car (5 adults and a boot full of stuff). My car had a set of disks and pads with about 2000 miles on them. I'm not certain about the brand of disks, but the pads were from a reputable supplier. I believe my braking system to be well maintained and properly set up.
Otley and Ilkley in West Yorkshire have some very long and twisty down hill sections (more than 4 continous miles in some areas). I was clearly not able to brake as well as I would under other driving conditions. By using the engine breaking method in combination with fairly modest pulses of breaking, I was able to control our descent without too much of a problem. However on two occasions where there were particulary long downhill sections, I noticed a reduction in breaking and a distinct hot metal smell when parking up at the bottom of the hill.
I have never had brake fade resulting from "spirited" driving, but I do think it is possible to get some minor to moderate brake performance loss with a heavy load on sustained long downhill sections.
Despite all of this, I am far less concerned about brake performance under emergency stopping situations. I am more concerned with the ability of my tyres to avoid locking up and my suspension system to enable me to retain control if I have to swerve.
Thanks
Chris
I have experienced some loss of breaking performance in my 1978 Dolomite 1850.
This occured on some very hot summer days this year with a heavily loaded car (5 adults and a boot full of stuff). My car had a set of disks and pads with about 2000 miles on them. I'm not certain about the brand of disks, but the pads were from a reputable supplier. I believe my braking system to be well maintained and properly set up.
Otley and Ilkley in West Yorkshire have some very long and twisty down hill sections (more than 4 continous miles in some areas). I was clearly not able to brake as well as I would under other driving conditions. By using the engine breaking method in combination with fairly modest pulses of breaking, I was able to control our descent without too much of a problem. However on two occasions where there were particulary long downhill sections, I noticed a reduction in breaking and a distinct hot metal smell when parking up at the bottom of the hill.
I have never had brake fade resulting from "spirited" driving, but I do think it is possible to get some minor to moderate brake performance loss with a heavy load on sustained long downhill sections.
Despite all of this, I am far less concerned about brake performance under emergency stopping situations. I am more concerned with the ability of my tyres to avoid locking up and my suspension system to enable me to retain control if I have to swerve.
Thanks
Chris