Ceramic brake pads in the wet
Discussion
Is it common for ceramic brake pads to not work at all when it's very wet? I fitted new discs and pads all round and when it's very wet and especially at motorway speeds, the brakes are almost non existent. Applying a lot of pressure does slow you down slowly and it will then bite all of a sudden, usually the drivers side first. Quite scary and I'm afraid I'll end up in a ditch.
t the bed moment (I was only doing about 10mph)Acidrop said:
Is it common for ceramic brake pads to not work at all when it's very wet? I fitted new discs and pads all round and when it's very wet and especially at motorway speeds, the brakes are almost non existent. Applying a lot of pressure does slow you down slowly and it will then bite all of a sudden, usually the drivers side first. Quite scary and I'm afraid I'll end up in a ditch.
That sounds extremely dangerous.E-bmw said:
That can't be right!
It certainly doesn't feel right. In the dry and from cold they always perform as you'd expect. Great stopping power, but in the wet it's a different story. And it will happen the whole time meaning you have to constantly apply the brakes to make sure you've got any stopping power.I would like to change them but read that ceramic pads seem to do this across the board, and I love not having a buildup of brake dust all over my alloys. Hmmm, have clean alloys and crash or have dirty alloys and live. Choices choices...
Kawasicki said:
Yes, Ceramic brakes can be less than optimal in the wet. Some cars have a function where the brakes are automatically applied regularly in the wet to help clear water. The brake applications are obviously very gentle, but they do work.
Gentle application of my brakes in the wet does absolutely nothing. Lol. I have to apply considerable force for it to just start slowing down and then push some more before the brakes will return to normal, causing a brown underpants moment every time. Why do ceramic pads do this, do you know?
Acidrop said:
Gentle application of my brakes in the wet does absolutely nothing. Lol. I have to apply considerable force for it to just start slowing down and then push some more before the brakes will return to normal, causing a brown underpants moment every time.
The "gentle application" that Kawasicki is talking about is done automatically by the ABS system (on cars with this feature) to keep the discs clear of water. It doesn't provide any noticeable braking effort.Old (70s-80s) motorbikes with stainless steel discs suffered from this problem. Apply the brakes in wet conditions and almost nothing would happen for a few revolutions of the wheel, by which time you'd almost pulled the lever back to the bar as panic set in, so as the discs dried and maximum braking was suddenly applied it became even more exciting. The workaround was exactly the same, a gentle squeeze of the brake every minute or so to clear the disc, though obviously a manual operation.
A quick search suggests that 'ceramic' pads are simply an alternative to the more organic and metallic pads I'm used to and don't have any fundamental differences. I don't see any reason why ceramic pads would have the extreme lack of braking you describe in wet conditions. Do you have brake cooling ducts or similar that might be throwing water spray over the brake rotors?
I think pad edges play a large part in clearing water from the rotors. Some of the ceramic pads I saw on the web had tapered edges that might be more prone to riding up on a layer of water. Anything unusual about the shape of the pads you're using?
I think pad edges play a large part in clearing water from the rotors. Some of the ceramic pads I saw on the web had tapered edges that might be more prone to riding up on a layer of water. Anything unusual about the shape of the pads you're using?
It’s not just ceramic pads that can exhibit this behaviour, both my Evoras were terrible for it.
Chances are it’s just that your car is prone to firing water at the discs and that by switching to a more aggressive pad compound you’ve highlighted an issue that you wouldn’t have noticed with the better cold friction or bite of the standard pad
Chances are it’s just that your car is prone to firing water at the discs and that by switching to a more aggressive pad compound you’ve highlighted an issue that you wouldn’t have noticed with the better cold friction or bite of the standard pad
GreenV8S said:
I think pad edges play a large part in clearing water from the rotors. Some of the ceramic pads I saw on the web had tapered edges that might be more prone to riding up on a layer of water. Anything unusual about the shape of the pads you're using?
Many (most?) standard organic pads have chamfered edges as well. It helps to reduce brake noise.GreenV8S said:
A quick search suggests that 'ceramic' pads are simply an alternative to the more organic and metallic pads I'm used to and don't have any fundamental differences. I don't see any reason why ceramic pads would have the extreme lack of braking you describe in wet conditions. Do you have brake cooling ducts or similar that might be throwing water spray over the brake rotors?
I think pad edges play a large part in clearing water from the rotors. Some of the ceramic pads I saw on the web had tapered edges that might be more prone to riding up on a layer of water. Anything unusual about the shape of the pads you're using?
Not that I've noticed. These are TRW Dtec pads and they are supposed to be good. About the cooling ducts, I'm not sure but will have a look. My old stock discs and pads never had this problem, it's only since I've fitted the new discs and pads. I do have drilled Zimmermann discs now though which I'm not sure if it's making things worse.I think pad edges play a large part in clearing water from the rotors. Some of the ceramic pads I saw on the web had tapered edges that might be more prone to riding up on a layer of water. Anything unusual about the shape of the pads you're using?
Apologies for resurrecting this thread but grateful for opinions.
A lot of threads talk about CCBs in the wet with regards to lack of bite etc. Does everyone also find the abs kicks in very early making it hard to modulate?
I've gone from Porsche 991 CCBs where I thought it was the weight distribution as even on steals they required some preloading and finesse so as to not unsettle the car. Now with BMW CCBs I notice the same in the wet that the abs triggers way too early and I can't quite get that threshold braking accurately when driving spiritedly in the wet.
Are there any tips for getting the maximum braking in the wet and keeping out of the abs zone?
Thanks
A lot of threads talk about CCBs in the wet with regards to lack of bite etc. Does everyone also find the abs kicks in very early making it hard to modulate?
I've gone from Porsche 991 CCBs where I thought it was the weight distribution as even on steals they required some preloading and finesse so as to not unsettle the car. Now with BMW CCBs I notice the same in the wet that the abs triggers way too early and I can't quite get that threshold braking accurately when driving spiritedly in the wet.
Are there any tips for getting the maximum braking in the wet and keeping out of the abs zone?
Thanks
Gassing Station | Suspension, Brakes & Tyres | Top of Page | What's New | My Stuff