brake pedal not so good
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brake pedal not so good
Hi all,
Can anyone say if they have the same brake pedal feel as my 2008 gt speed.
Brakes work brilliantly at low speed ie around town, light press/touch and they start to bite and never have to force pedal to floor.
However, at speed sy 70 plus if you want to do a quick stop as traffic stops in front of you unexpectedly, No repeat No emergency stop requires just firm braking .....the pedal travels almost to the floor and the car just slows down gracefully. Then as your *** starts to open an s4it your self as the queue is getting very close you end up pressing the pedal to the floor which is about 1 inch further travel. At that moment the car stands on its nose and you end up doing almost an emergency stop.
Any one got and insight into this....please.
Can anyone say if they have the same brake pedal feel as my 2008 gt speed.
Brakes work brilliantly at low speed ie around town, light press/touch and they start to bite and never have to force pedal to floor.
However, at speed sy 70 plus if you want to do a quick stop as traffic stops in front of you unexpectedly, No repeat No emergency stop requires just firm braking .....the pedal travels almost to the floor and the car just slows down gracefully. Then as your *** starts to open an s4it your self as the queue is getting very close you end up pressing the pedal to the floor which is about 1 inch further travel. At that moment the car stands on its nose and you end up doing almost an emergency stop.
Any one got and insight into this....please.
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Joined: Oct 2019
Posts: 159
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Hi all,
Can anyone say if they have the same brake pedal feel as my 2008 gt speed.
Brakes work brilliantly at low speed ie around town, light press/touch and they start to bite and never have to force pedal to floor.
However, at speed sy 70 plus if you want to do a quick stop as traffic stops in front of you unexpectedly, No repeat No emergency stop requires just firm braking .....the pedal travels almost to the floor and the car just slows down gracefully. Then as your *** starts to open an s4it your self as the queue is getting very close you end up pressing the pedal to the floor which is about 1 inch further travel. At that moment the car stands on its nose and you end up doing almost an emergency stop.
Any one got and insight into this....please.
Can anyone say if they have the same brake pedal feel as my 2008 gt speed.
Brakes work brilliantly at low speed ie around town, light press/touch and they start to bite and never have to force pedal to floor.
However, at speed sy 70 plus if you want to do a quick stop as traffic stops in front of you unexpectedly, No repeat No emergency stop requires just firm braking .....the pedal travels almost to the floor and the car just slows down gracefully. Then as your *** starts to open an s4it your self as the queue is getting very close you end up pressing the pedal to the floor which is about 1 inch further travel. At that moment the car stands on its nose and you end up doing almost an emergency stop.
Any one got and insight into this....please.
To confirm this try doing your high speed braking attempt, but instead of pressing the pedal that final inch to get proper retardation, come off the pedal completely then immediately press it again.
My guess is that second prod will result in proper braking.
That's because the time between coming off the pedal having taken up the slack, and the second press, is sufficiently short that no significant knock-back can occur.
In my experience knock-back occurs as a consequence of either warped disks or worn wheel bearings.
The reason it doesn't seem to happen around town is because the forces are lower and generally you're on and off the brakes so frequently that knock-back can't take effect before it is corrected.
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That sounds like pad knock-back. i.e. something is pushing the pistons back into the calliper marginally further than is intended, and you have to take up that extra displacement and move the pistons/pads back towards the disk before the brakes can start to work.
To confirm this try doing your high speed braking attempt, but instead of pressing the pedal that final inch to get proper retardation, come off the pedal completely then immediately press it again.
My guess is that second prod will result in proper braking.
That's because the time between coming off the pedal having taken up the slack, and the second press, is sufficiently short that no significant knock-back can occur.
In my experience knock-back occurs as a consequence of either warped disks or worn wheel bearings.
The reason it doesn't seem to happen around town is because the forces are lower and generally you're on and off the brakes so frequently that knock-back can't take effect before it is corrected.
To confirm this try doing your high speed braking attempt, but instead of pressing the pedal that final inch to get proper retardation, come off the pedal completely then immediately press it again.
My guess is that second prod will result in proper braking.
That's because the time between coming off the pedal having taken up the slack, and the second press, is sufficiently short that no significant knock-back can occur.
In my experience knock-back occurs as a consequence of either warped disks or worn wheel bearings.
The reason it doesn't seem to happen around town is because the forces are lower and generally you're on and off the brakes so frequently that knock-back can't take effect before it is corrected.
Alas, Ive had the discs and pads changed at Bentley Glasgow, service and MOT and she still does it.
However thats a good idea about pumping the brakes. At the exact time you need a good pedal you don't have time to test pumping. So I will go out on a quiet road and do some pumping and see what occurs. 👍
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I'm not really advocating pumping the brakes, rather a quick off and back on.
Even so, you're right to want to do it somewhere quiet.
If disks have been changed (and done properly, and checked with a DTI after fitment) then the other cause is a wheel bearing allowing the rotating part of the hub to wander slightly, but I've previously only known it to happen on cars with adjustable taper roller bearings.
That said, if it is a bearing then you won't need to repeat it at high speed - instead, at slow speed steer the car hard from side to side as if in a slalom. That will put enough lateral force on the bearings to provoke pad knock back if it's going to happen.
As an aside: Some years ago I was competing at Curborough and a couple of chaps with an OMS or similar bike powered single seater, were constantly moaning about the brakes needing a quick confidence dab before each fast corner. Not what you want. Anyway, having listened to everything that they'd done to the brakes in a fruitless attempt to cure the problem, I asked whether they had checked the wheel bearings.
Suddenly the light went on in their minds, and sure enough, just tightening the bearings cured the problem.
Even so, you're right to want to do it somewhere quiet.
If disks have been changed (and done properly, and checked with a DTI after fitment) then the other cause is a wheel bearing allowing the rotating part of the hub to wander slightly, but I've previously only known it to happen on cars with adjustable taper roller bearings.
That said, if it is a bearing then you won't need to repeat it at high speed - instead, at slow speed steer the car hard from side to side as if in a slalom. That will put enough lateral force on the bearings to provoke pad knock back if it's going to happen.
As an aside: Some years ago I was competing at Curborough and a couple of chaps with an OMS or similar bike powered single seater, were constantly moaning about the brakes needing a quick confidence dab before each fast corner. Not what you want. Anyway, having listened to everything that they'd done to the brakes in a fruitless attempt to cure the problem, I asked whether they had checked the wheel bearings.
Suddenly the light went on in their minds, and sure enough, just tightening the bearings cured the problem.
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Registered User
Joined: May 2010
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I'm not really advocating pumping the brakes, rather a quick off and back on.
Even so, you're right to want to do it somewhere quiet.
If disks have been changed (and done properly, and checked with a DTI after fitment) then the other cause is a wheel bearing allowing the rotating part of the hub to wander slightly, but I've previously only known it to happen on cars with adjustable taper roller bearings.
That said, if it is a bearing then you won't need to repeat it at high speed - instead, at slow speed steer the car hard from side to side as if in a slalom. That will put enough lateral force on the bearings to provoke pad knock back if it's going to happen.
As an aside: Some years ago I was competing at Curborough and a couple of chaps with an OMS or similar bike powered single seater, were constantly moaning about the brakes needing a quick confidence dab before each fast corner. Not what you want. Anyway, having listened to everything that they'd done to the brakes in a fruitless attempt to cure the problem, I asked whether they had checked the wheel bearings.
Suddenly the light went on in their minds, and sure enough, just tightening the bearings cured the problem.
Even so, you're right to want to do it somewhere quiet.
If disks have been changed (and done properly, and checked with a DTI after fitment) then the other cause is a wheel bearing allowing the rotating part of the hub to wander slightly, but I've previously only known it to happen on cars with adjustable taper roller bearings.
That said, if it is a bearing then you won't need to repeat it at high speed - instead, at slow speed steer the car hard from side to side as if in a slalom. That will put enough lateral force on the bearings to provoke pad knock back if it's going to happen.
As an aside: Some years ago I was competing at Curborough and a couple of chaps with an OMS or similar bike powered single seater, were constantly moaning about the brakes needing a quick confidence dab before each fast corner. Not what you want. Anyway, having listened to everything that they'd done to the brakes in a fruitless attempt to cure the problem, I asked whether they had checked the wheel bearings.
Suddenly the light went on in their minds, and sure enough, just tightening the bearings cured the problem.
it would would appear that the last inch before the floor triggers the EBS which has no finite control its either on or off hence the car stands on its nose. The Continental Gt has another safety feature. If you loose the pedal all together for what ever reason if you lift up and hold the parking brake switch at more that walking pace the EBS is triggered and you come to a controlled dead stop. The think is I don't want the EBS triggering because the brake pedal has neared the floor.
As Bentley Glasgow is in town there is no where to do high speed braking. Even at 50 mph my brakes are fantastic. Its only higher speeds that have this issue. ???
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