Oversensitive ABS ?

[cuprablue]

Do you guys find it easy to get the ABS to kick in from a relatively low speed (say up to 20mph) ?

I've had (what I assume to be) the ABS kick in twice now. Once was coming round a corner to find a guy on my side of the road. The second time I was just messing around to see how quickly I could do an emergency stop. Both days were cold but dry and I was quite surprised to feel the ABS come in to action at such a low speed to be honest.

I have to say the feeling is quite unpleasant at the pedal. Feels like I'd imagine it would if the brake pads were running over some spokes or something. I know my discs are quite worn and will need replacing in the not too distant future but other than that they feel smooth and still have good initial bite to them. In fact the first time it happened I thought something had broken.

cuprablue

 

[WaveyDaveyGravy]

There could be other factors involved here, like black ice, diesel on the road (esp. on a corner). I've been surprised a couple of times too, but as long as it's working there's not a lot anyone can do. It's there to help and the absolute worst that can happen is that your braking distance will be longer (but you'll still have control).

 

[cuprablue]

There could be other factors involved here, like black ice, diesel on the road (esp. on a corner). I've been surprised a couple of times too, but as long as it's working there's not a lot anyone can do. It's there to help and the absolute worst that can happen is that your braking distance will be longer (but you'll still have control).

True, but I'm a little worried that it may be something else also as I don't actually recall seeing the ABS light come up on the dash.

But then again I never notice the Traction control light either unless I am looking right at it when I floor it.


Is it possible for some kind of brake fault to cause a similar feeling through the pedals? only on heavy braking?

cuprablue

 

[WaveyDaveyGravy]

That's good, you were looking where you were going rather than the light on the dash! The judder as you know is built in for ABS, and I can't think of anything else that would be similar - warped discs, dodgy pads etc. I'm no mechanic though and if you have any doubts at all get in touch with a dealer who will be able to set your mind at rest.

 

[NeilC]

It's the eba that narks me. Doing a perfectly reasonable if a little sharp stop and it slams the break pedal to the floor making the esp come on which lengthens the stop. I can press the pedal myself if i wanted!

 

[Reg]

Eh? Surely the judder is the ABS working - you feel the pulse of the brakes working throught the pedal. If the ABS isn't on the pedal won't pulse. Agree its not a pleasant feeling, and why its recommended that people try their ABS somewhere quiet so that they know what it feels like. There have been more than one or two reports where someone feels the pulsing, thinks its wrong and lifts off the brakes. Not ideal! Also, chances are you haven't seen the light coming on because if you are in a situation where the ABS is activated, your concentration is on something other than a light on the dash!

The way the road surfaces are at this time of year, even when dry they are not very grippy. If you braked hard whilst cornering you might have only locked one wheel and that was enough to wake the ABS. Its only going to get worse too, the road salt is mixed with molasses sugar to help it 'stick' to the road and stop it being washed away by rain as soon as its down (which is what happened a couple of years ago and the councils were blamed for not putting salt down quick enough). Trouble is it never fully dries so even when the roads appear dry the surface is slick with this salt/sugar mix.

 

[Brucel]

To be perfectly honest I have to try really hard on track to get the ABS on but on the road its always on and off and the ESP is on a lot at the moment with the greasy roads....

Don't think it is anything to worry about.

I'd rather have it kick in that not....

 

[cuprablue]

Eh? Surely the judder is the ABS working - you feel the pulse of the brakes working throught the pedal. If the ABS isn't on the pedal won't pulse. Agree its not a pleasant feeling, and why its recommended that people try their ABS somewhere quiet so that they know what it feels like. There have been more than one or two reports where someone feels the pulsing, thinks its wrong and lifts off the brakes. Not ideal! Also, chances are you haven't seen the light coming on because if you are in a situation where the ABS is activated, your concentration is on something other than a light on the dash!

The way the road surfaces are at this time of year, even when dry they are not very grippy. If you braked hard whilst cornering you might have only locked one wheel and that was enough to wake the ABS. Its only going to get worse too, the road salt is mixed with molasses sugar to help it 'stick' to the road and stop it being washed away by rain as soon as its down (which is what happened a couple of years ago and the councils were blamed for not putting salt down quick enough). Trouble is it never fully dries so even when the roads appear dry the surface is slick with this salt/sugar mix.

To be honest this is my first experience of an ABS equiped car, (I've been a biker most of my life and the few cars I've had so far have been old bangers), so I wasn't quite sure what to expect. Most of what I've read has lead me to believe that their would be a gentle pulsing at the peddle so I was a bit shocked at how violent the feel through the peddle was. I'm intriged by this EPS bit as now I think about it the peddle does seem to suddenly "give" when this has happened, and that's the feel that's made me thnk that something was wrong. If this is the EPS kicking in then I'll not worry about it and just look in to getting the discs and pads changed in the new year sometime because they look very close to the minimum thickness at the moment.


As for road vs track surfaces. I know exactly what you mean, I've done quite a few bike track days in my time and to be honest it was the main reason I gave up biking. After having ridden on a track it makes you realise just how dangerous riding on normal roads really is. There is next to no real grip (especially at this time of year) and you can't ever push your bike anywhere near it's real limits so it all becomes a bit boring and pointless. Then of course there are all the car drivers who are out to kill you !!

cuprablue

 

[Reg]

EBA, not EPS (Emergency Brake Assist). My Dad had never triggered his ABS, so last winter we went to an empty corner of a greasy carpark and he had a try - same as you, he was expecting a little pulse through the pedal but was amazed at the strength of the pulsing, and the noise too! Better to be surprised then, than when the brown stuff has hit the spinning thing.

I can totally sympathise on the bike front. I have recently sold mine and I doubt I will be riding on the road again. After doing 2 years commuting all year round I'd had enough of bad weather, so stuck to fair weather only. I love track days, and when I get another bike it will just be for track use. I know 4 people killed on their bikes this year in seperate incidents, none attributed to their fault, all involving a third party in a car.

This time of year, add that slippery stuff to the road and its a disaster waiting to happen.

 

[v8rush]

I have to say the feeling is quite unpleasant at the pedal. Feels like I'd imagine it would if the brake pads were running over some spokes or something. I know my discs are quite worn and will need replacing in the not too distant future but other than that they feel smooth and still have good initial bite to them. In fact the first time it happened I thought something had broken.

Yeah, it's quite scary, as I found my initial reaction was to let _off_ the brakes because of the pulsing. Definitely worth 'playing' with it a couple of times so that when you really need it, it's not a surprise. OTOH, when you're sliding along in a car without ABS, the initial reaction is for your brain to say "lift and reapply", but your foot just stays planted...