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To ABS or not to ABS....


Gweiloman

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that is nonsense to say abs is killing the brake feel. abs is not a robotic system that brakes for you. it just applies the braking pressure on and off when the sensors send signals stating that tire/tires are skidding.

abs comes in effect when the tire is skidding and as it is a hydraulic system, it does not matter much if there is an extra length of hoses on ABS system as long as it is not 10 meters of extra length especially if they are braided steel lines.

also it is plain misleading to say ABS does not prevent accidents! so all those engineers, regulators and inventors of ABS are stupid then to create such a system and spend billions on it? i dont think so someone with respect for human life and fellow riders can say that allegedly.

i use a bike with ABS system now and brakes gives me great modulation and feedback.

only setback of an ABS system is longer braking distance if it comes on during hard braking but that is only if the tires skid.

if you know how to brake with a non abs system and use your abs brakes accordingly, an abs system stops at the same distance if you dont activate the ABS.

only on the track i can say a conventional abs system might be limiting as you slide there etc but then makers create race abs systems and put them on their expensive track monsters and they dont limit the bike, or basically you have an on/off switch so you can keep the ABS off.

ll2, I believe that mania is making the point that they definitely kill the feel at the instance where they start intervening. Which is at the ragged edge where a really good rider is at. Not on the street going to 7-11 level.

Or perhaps I misunderstood his posts.

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Otherwise I respect the fact you don't require and even less want ABS. At my skill level having that safety net is a plus. Perhaps in the future there will be bikes that have ABS but can be completely disabled at the dealer for someone who has completed proper training or has a racing license or something...

Yes Dave & as I said in all my posts it is my opinion of what I want

in a brake system. I in no way disparage those that want ABS

As for the future having an ABS system that can be disabled I do not think it is possible.

As the system is there or not. Even if one turns off the electronic sensor which kicks in the

ABS action it cannot undo the plumbing the fluid still need to travel thru.

Which is why in Aussieroamings Post he said he could not detect any difference. Albeit his bike

is current & not a future example...but I do not see it ever being transparent.

For myself I can only say no matter the cost of any future new bike I may want ABS would not stop me from buying it...but it would be ripped

out by its short hairs faster than one can say lickety split & replaced with a good quality components straight system

The biggest problem of course will be software related & how it may or may not complain at the missing info

Edited by mania
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Otherwise I respect the fact you don't require and even less want ABS. At my skill level having that safety net is a plus. Perhaps in the future there will be bikes that have ABS but can be completely disabled at the dealer for someone who has completed proper training or has a racing license or something...

Yes Dave & as I said in all my posts it is my opinion of what I want

in a brake system. I in no way disparage those that want ABS

As for the future having an ABS system that can be disabled I do not think it is possible.

As the system is there or not. Even if one turns off the electronic sensor which kicks in the

ABS action it cannot undo the plumbing the fluid still need to travel thru.

Which is why in Aussieroamings Post he said he could not detect any difference. Albeit his bike

is current & not a future example...but I do not see it ever being transparent.

For myself I can only say no matter the cost of any future new bike I may want ABS would not stop me from buying it...but it would be ripped

out by its short hairs faster than one can say lickety split & replaced with a good quality components straight system

The biggest problem of course will be software related & how it may or may not complain at the missing info

I could be wrong, but we both agree that the brake fluid is incompressible, right?

So one molecule presses against the next and either moves it as much as the original molecule was moved or it stops moving, right?

So how does the length of the system matter? I keep going back to the front brake question. With dual discs, the manufacturer often runs another line up and over the fender to the secondary disk. If feel/performance would be improved using a T-fitting and shorter lines, why don't they do that?

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that is nonsense to say abs is killing the brake feel. abs is not a robotic system that brakes for you. it just applies the braking pressure on and off when the sensors send signals stating that tire/tires are skidding.

abs comes in effect when the tire is skidding and as it is a hydraulic system, it does not matter much if there is an extra length of hoses on ABS system as long as it is not 10 meters of extra length especially if they are braided steel lines.

also it is plain misleading to say ABS does not prevent accidents! so all those engineers, regulators and inventors of ABS are stupid then to create such a system and spend billions on it? i dont think so someone with respect for human life and fellow riders can say that allegedly.

i use a bike with ABS system now and brakes gives me great modulation and feedback.

only setback of an ABS system is longer braking distance if it comes on during hard braking but that is only if the tires skid.

if you know how to brake with a non abs system and use your abs brakes accordingly, an abs system stops at the same distance if you dont activate the ABS.

only on the track i can say a conventional abs system might be limiting as you slide there etc but then makers create race abs systems and put them on their expensive track monsters and they dont limit the bike, or basically you have an on/off switch so you can keep the ABS off.

ll2, I believe that mania is making the point that they definitely kill the feel at the instance where they start intervening. Which is at the ragged edge where a really good rider is at. Not on the street going to 7-11 level.

Or perhaps I misunderstood his posts.

Myth: ABS modulates system pressure whenever you apply the brakes.

A lot of the rider bias against ABS is that the system is always active, modulating your brakes in all stopping instances and thereby affecting the riding experience. On the contrary, ABS only kicks in to prevent wheel lockup, such as during panic-stop situations or when you encounter black ice.

At other times, such as during typical controlled stops or slowing for corners, ABS does not affect how the brakes work.

ABS comes into the play when the tire is skidding not when you apply the brakes. If it is a system that controls all braking when you apply the brakes, it has to be a lot more expensive system.

there is a good article regarding myths about ABS here:

http://www.americanmotorcyclist.com/Features/RideReports/AntiLockBraking.aspx

Edited by ll2
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Great post mania.

This goes a long way towards explaining why racers do not want ABS. Braking points are measured in inches (I could be mistaken but I remember watching a video of Casey Stoner walking a track and telling how he is looking for a point (to start braking) the size of a 50 cent coin).

On the road however, do we need such precision and feel for normal day to day riding or even long distance touring? Genuine question by the way.

One other thing - there is also a video of Pedrosa braking into a corner with his rear wheel off the ground. Is this possible with ABS brakes?

Hi Gweiloman

IMHO & for myself yes I want the best braking system I can have.

It is not just a matter of precision but function.

No Pedrosa nor anyone else could have used the front brake effectively to the point of lifting the rear without ABS kicking in. Remember ABS is not unlocking a skid & while Dani

of course is not locking his front wheel it is spinning/rotational speed at a large difference at that point than to his rear wheel. That is what ABS monitors rotational speeds of the two wheels

It decides what it thinks is a big enough difference & then kicks in/takes over/takes away his ability to fully use his brakes.

Mania;

Would you think that the ABS interferes with the feedback before actuation? I understand that there are many levels of ABS, but just take the general ones offered in LOS. Do they mask the feedback up to the point where you'd lock your brakes (and then they actuate)? Or am I misunderstanding the operation and in actuality the fluid is ALWAYS being modulated by the ABS system rather than just under possible skidding conditions? I also wonder (not trying to pick a fight or anything...honest!) how much the added steel lines effect the feel. After all the braking fluid should be incompressible and thus the amount of force applied should be constant...right? Isn't that why some bikes have the secondary front calliper ran of the primary one rather than having a "T" junction?

Also, do racers not need it as they know how to ride to not get into the skidding zone and thus it is unnecessary weight?

Dave,

Yes of course it has interfered by masking the necessary feedback that comes with what I described in my post as a great braking system.

As to does it mask to a point of lock I would guess that depends on the rider. For a poor rider it does not matter much as they are just grabbing a handful & hoping for the best. It would not mask the limit for me but it has taken away a useful indicator & useful amount of braking. Once it decides I am too close to optimum braking/ or what it perceives as speed differences being too great between the two wheels it takes over robbing me of that point which is actually further than where the ABS kicks in. Of course ABS is not designed to act when a skid occurs but before it. How far before? Well as a safety device it is going to err on the side of what it thinks is safe/prudent

Steel lines help the feel not because of fluid being uncompressible

But because the line itself under high stress will slightly expand & actually physically move about. You can see it yourself on a rubber exterior type brake line especially the front brake. Have a pal press fast & tight/hold release repeat while you squat down by the fork & watch the rubber type line move. But this is a small fine tuning & part of the whole better system not even noticeable to many I would guess. But still part of the whole.

Racers do not want it not due to the weight as all factories easily break weight minimums & many times need to add weight. But it is just impossible to ride in those conditions with it. Again due to the ABS checking rotational speeds & whether they match or are within the limits the system was designed to take over at. Yes they could probably adjust software to be extremely on the limit but why? Because as you said these folks know how to ride.

You said they know how to ride to not get into the skidding zone Is this not something

Every rider should learn/know? I think it is. I also think if a rider does accidentally get a lock started they should know to quickly release & restart the braking process.

Same as a rider heading into a turn & then decides they are going too fastInstead of target fixating & heading to the outside of the turn they should instinctively know what needs to be done where to lookwhere to go.

Again this is all my opinion.This is what I know & what I want.

What others want/need is up to them to decide. wink.png

Mania, I think you might be confusing ABS with anti-stoppie. I lifted the rear wheel on my ABS equipped bike a couple of weeks ago because it has ABS only, not anti-stoppie. ABS (alone) just monitors if the front wheel is locked and reduces braking based on that, it doesn't compare the rotation of the 2 wheels to determine if the rear is in the air, that's what anti-stoppie does. Of course, a bike with ABS and anti-stoppie would do that.

With a perfect road and hot sticky tyres, it should be able to lift the rear tyre on an ABS bike (if it doesn't have anti-stoppie) without the ABS kicking in. You'd just have to brake hard without the front wheel locking up. Granted, in my case the ABS kicked in (greasy BKK road) at roughly the same time as the rear wheel lifted, but had the conditions been better and my front tyre not locked then the rear would still have lifted.

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Otherwise I respect the fact you don't require and even less want ABS. At my skill level having that safety net is a plus. Perhaps in the future there will be bikes that have ABS but can be completely disabled at the dealer for someone who has completed proper training or has a racing license or something...

Yes Dave & as I said in all my posts it is my opinion of what I want

in a brake system. I in no way disparage those that want ABS

As for the future having an ABS system that can be disabled I do not think it is possible.

As the system is there or not. Even if one turns off the electronic sensor which kicks in the

ABS action it cannot undo the plumbing the fluid still need to travel thru.

Which is why in Aussieroamings Post he said he could not detect any difference. Albeit his bike

is current & not a future example...but I do not see it ever being transparent.

For myself I can only say no matter the cost of any future new bike I may want ABS would not stop me from buying it...but it would be ripped

out by its short hairs faster than one can say lickety split & replaced with a good quality components straight system

The biggest problem of course will be software related & how it may or may not complain at the missing info

I could be wrong, but we both agree that the brake fluid is incompressible, right?

So one molecule presses against the next and either moves it as much as the original molecule was moved or it stops moving, right?

So how does the length of the system matter? I keep going back to the front brake question. With dual discs, the manufacturer often runs another line up and over the fender to the secondary disk. If feel/performance would be improved using a T-fitting and shorter lines, why don't they do that?

Dave...Read my response about your front brake line question. Yes brake fluid is incompressible. Almost every component in braking system, including the ABS components are incompressible too. But that only applies to static systems. You mentioned line length above, but there are many more factors than just the length of a hose.

The lines / system are designed in such a way that under dynamic situations that there is no significant restriction or difference in pressure at any point. In an ABS system it is actually designed to pulsate many times a second which is about as dynamic as you can get. You certainly could not modulate your hand that quickly.

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Mania, I think you might be confusing ABS with anti-stoppie. I lifted the rear wheel on my ABS equipped bike a couple of weeks ago because it has ABS only, not anti-stoppie. ABS (alone) just monitors if the front wheel is locked and reduces braking based on that, it doesn't compare the rotation of the 2 wheels to determine if the rear is in the air, that's what anti-stoppie does. Of course, a bike with ABS and anti-stoppie would do that.

With a perfect road and hot sticky tyres, it should be able to lift the rear tyre on an ABS bike (if it doesn't have anti-stoppie) without the ABS kicking in. You'd just have to brake hard without the front wheel locking up. Granted, in my case the ABS kicked in (greasy BKK road) at roughly the same time as the rear wheel lifted, but had the conditions been better and my front tyre not locked then the rear would still have lifted.

I do not know your exact system Jonny & you could be right...But then again as you said your ABS

did in fact kick in at the point of rear wheel lift wink.png

But that aside this portion we are now talking about is the very last complaint as it is the last thing to happen.

But it is just one portion of the overall complaint.

I do not consider an ABS works after a wheel is locked but actually sometime before. To what ever degree it is programed to

start...this feel I can only describe as wooden

But again we now enter a space of trying to describe a pinch wink.png

Also I should continue to say ABS for those that want it or even feel it a form of insurance is a good thing.

I in no way begrudge anyone of anything they may want/need.

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In an ABS system it is actually designed to pulsate many times a second which is about as dynamic as you can get. You certainly could not modulate your hand that quickly.

I was not going to mention this feature but since you brought it up...

I agree & it is one of the final line complaints.

You are right when you say

You certainly could not modulate your hand that quickly.

But who would want too? This series of quick dashed braking is what a mechanical system

has to do as it is unsophisticated...

a human (trained human I should say) has a much better system at their disposal of a rapid constant pressure to the point of limit.

At which point a slight release & reapplying of pressure is far better IMO

Instead of being along for the ride of quick stabs at the brake.

I do not know about others but if something takes away my total control then my mental state becomes confused

Because in this split second of time I am not thinking I am reacting as I have always reacted.

Now something totally foreign has been introduced & things are not proceeding as they should. A moment of confusion ensues

Having said that I imagine one could be trained to function within ABS induced states.

I have no desire to be that one but I am sure it could be done ;)

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Great post mania.

This goes a long way towards explaining why racers do not want ABS. Braking points are measured in inches (I could be mistaken but I remember watching a video of Casey Stoner walking a track and telling how he is looking for a point (to start braking) the size of a 50 cent coin).

On the road however, do we need such precision and feel for normal day to day riding or even long distance touring? Genuine question by the way.

One other thing - there is also a video of Pedrosa braking into a corner with his rear wheel off the ground. Is this possible with ABS brakes?

Hi Gweiloman

IMHO & for myself yes I want the best braking system I can have.

It is not just a matter of precision but function.

No Pedrosa nor anyone else could have used the front brake effectively to the point of lifting the rear without ABS kicking in. Remember ABS is not unlocking a skid & while Dani

of course is not locking his front wheel it is spinning/rotational speed at a large difference at that point than to his rear wheel. That is what ABS monitors rotational speeds of the two wheels

It decides what it thinks is a big enough difference & then kicks in/takes over/takes away his ability to fully use his brakes.

Mania;

Would you think that the ABS interferes with the feedback before actuation? I understand that there are many levels of ABS, but just take the general ones offered in LOS. Do they mask the feedback up to the point where you'd lock your brakes (and then they actuate)? Or am I misunderstanding the operation and in actuality the fluid is ALWAYS being modulated by the ABS system rather than just under possible skidding conditions? I also wonder (not trying to pick a fight or anything...honest!) how much the added steel lines effect the feel. After all the braking fluid should be incompressible and thus the amount of force applied should be constant...right? Isn't that why some bikes have the secondary front calliper ran of the primary one rather than having a "T" junction?

Also, do racers not need it as they know how to ride to not get into the skidding zone and thus it is unnecessary weight?

Dave,

Yes of course it has interfered by masking the necessary feedback that comes with what I described in my post as a great braking system.

As to does it mask to a point of lock I would guess that depends on the rider. For a poor rider it does not matter much as they are just grabbing a handful & hoping for the best. It would not mask the limit for me but it has taken away a useful indicator & useful amount of braking. Once it decides I am too close to optimum braking/ or what it perceives as speed differences being too great between the two wheels it takes over robbing me of that point which is actually further than where the ABS kicks in. Of course ABS is not designed to act when a skid occurs but before it. How far before? Well as a safety device it is going to err on the side of what it thinks is safe/prudent

Steel lines help the feel not because of fluid being uncompressible

But because the line itself under high stress will slightly expand & actually physically move about. You can see it yourself on a rubber exterior type brake line especially the front brake. Have a pal press fast & tight/hold release repeat while you squat down by the fork & watch the rubber type line move. But this is a small fine tuning & part of the whole better system not even noticeable to many I would guess. But still part of the whole.

Racers do not want it not due to the weight as all factories easily break weight minimums & many times need to add weight. But it is just impossible to ride in those conditions with it. Again due to the ABS checking rotational speeds & whether they match or are within the limits the system was designed to take over at. Yes they could probably adjust software to be extremely on the limit but why? Because as you said these folks know how to ride.

You said they know how to ride to not get into the skidding zone Is this not something

Every rider should learn/know? I think it is. I also think if a rider does accidentally get a lock started they should know to quickly release & restart the braking process.

Same as a rider heading into a turn & then decides they are going too fastInstead of target fixating & heading to the outside of the turn they should instinctively know what needs to be done where to lookwhere to go.

Again this is all my opinion.This is what I know & what I want.

What others want/need is up to them to decide. wink.png

Mania, I think you might be confusing ABS with anti-stoppie. I lifted the rear wheel on my ABS equipped bike a couple of weeks ago because it has ABS only, not anti-stoppie. ABS (alone) just monitors if the front wheel is locked and reduces braking based on that, it doesn't compare the rotation of the 2 wheels to determine if the rear is in the air, that's what anti-stoppie does. Of course, a bike with ABS and anti-stoppie would do that.

With a perfect road and hot sticky tyres, it should be able to lift the rear tyre on an ABS bike (if it doesn't have anti-stoppie) without the ABS kicking in. You'd just have to brake hard without the front wheel locking up. Granted, in my case the ABS kicked in (greasy BKK road) at roughly the same time as the rear wheel lifted, but had the conditions been better and my front tyre not locked then the rear would still have lifted.

Motorcycles use 2 Channel ABS which take information from both the front and rear wheel speeds. It compares the speed of those two and decides how to modulate the braking if there is a great enough difference in speed between the front and back wheel. In a stoppie where the front tire still had traction, the rear would be the one receiving help form the abs (if the rider was using the rear brake of course)

The think the anti stoppie systems you are referring to use 2 channel info and accelerometers or gyros to determine if the rear wheel is lifting.

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In an ABS system it is actually designed to pulsate many times a second which is about as dynamic as you can get. You certainly could not modulate your hand that quickly.

I was not going to mention this feature but since you brought it up...

I agree & it is one of the final line complaints.

You are right when you say

You certainly could not modulate your hand that quickly.

But who would want too? This series of quick dashed braking is what a mechanical system

has to do as it is unsophisticated...

a human (trained human I should say) has a much better system at their disposal of a rapid constant pressure to the point of limit.

At which point a slight release & reapplying of pressure is far better IMO

Instead of being along for the ride of quick stabs at the brake.

I do not know about others but if something takes away my total control then my mental state becomes confused

Because in this split second of time I am not thinking I am reacting as I have always reacted.

Now something totally foreign has been introduced & things are not proceeding as they should. A moment of confusion ensues

Having said that I imagine one could be trained to function within ABS induced states.

I have no desire to be that one but I am sure it could be done wink.png

I respect your point of view about ABS and on completely uniform dry roads (no sand or oil..etc) I agree with you that your hand is well trained to know the limits of traction for your bike. I think a lot of how well we ride and react to situations is based on how comfortable we are on the equipment we have. If you feel more comfortable with a non-abs system I cant argue that point. I feel better on a system with ABS because the road surfaces here are so varied, I feel it gives me a layer of security.

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In an emergency braking situation, I would most likely be focusing on escape routes, being rear ended, getting into the right gear and a multitude of other factors. It's nice to know that the ABS will be taking care of the braking side of things.

Not unlike in management - delegating is more efficient and effective than trying to do everything yourself.

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In an emergency braking situation, I would most likely be focusing on escape routes, being rear ended, getting into the right gear and a multitude of other factors. It's nice to know that the ABS will be taking care of the braking side of things.

Not unlike in management - delegating is more efficient and effective than trying to do everything yourself.

yep, totally agree. abs takes care the braking and you focus on other things like a fun ride.

in Thailand, doing everything by yourself is easier than delegating things or even from explaining people what to do!

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I respect your point of view about ABS and on completely uniform dry roads (no sand or oil..etc) I agree with you that your hand is well trained to know the limits of traction for your bike. I think a lot of how well we ride and react to situations is based on how comfortable we are on the equipment we have. If you feel more comfortable with a non-abs system I cant argue that point. I feel better on a system with ABS because the road surfaces here are so varied, I feel it gives me a layer of security.

Thank you 1Baddat I also respect your decision & reasoning for wanting ABS.

Brakes aside these road conditions here you mention are as you say so varied & can surprise any rider

regardless of experience. This again is why off road practice is so invaluable especially to learners but even to experienced riders

like the GP riders who train off road every year during the off season. It is to condition their reactions to events like either wheel

suddenly losing traction or even how it should feel when purposely sliding as they do under acceleration during turn exit

or rear wheel lift during deceleration during entry many times during a race.

Because the truth is the brakes are but a fraction of the total & many times using them at all during certain situations

would be the wrong choice.

Its all good & should all ultimately be fun

Thanks

Edited by mania
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When I got my GS I played around with ABS on and off. As I learned where the edge was with ABS off, at low speeds, I noticed that I was stopping in a shorter distance than with ABS on and activated. The difference at low speed is small; a few off/on cycles at between 15 and 40 km/h results in an inch or two max. Since then I have mainly ridden on road and up country with ABS on and I am sure I have forgotten where the edge is. I think Mania is spot on on feeling brakes; once ABS activates, I might as well be driving a one of my Landys...

I think some more precise language is needed to describe ABS. In any situation where a rider brakes hard enough to activate ABS, a skid would have occurred were ABS not available. That alone will effect better stopping with ABS, as the skid and recovery (if any) will lengthen the stopping distance. And as you all know, at high speeds, or in a corner, locking a wheel, especially the front might end in an accident. IMO, this will be a major contributor to the percentage decrease in fatal accidents cited from some report in an earlier post...

In situations where the rider hits the maximum braking without activating ABS, they will achieve the best braking distance, however, if ABS is activated, the off/on cycle will add a small distance to the total braking distance for each cycle it performs. I have tested this myself, and at least with me, on my bike, I can repeat this consistently. If I keep the same pressure on the calipers once ABS is actuated, I can hear the wheels start to slide on gravel or sand, but there is no significant locking and braking is good. If I reduce pressure until the ABS is deactivated, braking is now smoother and according to my totally unscientific measurements, slightly more effective.

If you activate ABS by braking too hard you and don't reduce pressure to get to the point that ABS deactivates, you will add a few inches to your stopping distance. That is why I often turn it off in heavy traffic. ABS is great for many reasons, but it is not a guarantee of the shortest stopping distance in all situations - especially if you rely on it from beginning to end of a braking manoeuvre. I think it is a dangerous mistake to consider ABS as a fool-proof solution to braking, and I would encourage people to test it as I did (or better - not hard to) if they can.

As an aside, I did the basic course with Off-Road Skills here in Thailand and after body position the first thing we were taught was sliding the back wheel at speed, followed by controlling a front wheel slide. With the front brake loaded, in 1st gear and half-clutch, slowly accelerate while increasing braking pressure until the front wheel locks up - try and keep vertical for as long as possible, releasing the brake when you pucker up a little too tightly. It takes a while, but eventually most students can manage close to 10 meters in a front-wheel skid. I now ride off-road with ABS off most of the time...

Ride safe...

I am not convinced that the two are comparable; a system for voluntary sharing of information and a method to avoid incident or potential incident. However, my bike has selectable ABS so I have an opinion on that...

I believe better riders that myself, of which there are many, prefer to be fully in charge and in touch with their bikes. Up-country, I keep it on, but if ever forced to ride downtown I will often turn it off. The extra few inches it takes if one actuates ABS is all you need to kiss a cage's backside... And yes, I know that means I am too close.

When riding downtown, I would have thought the reverse was better. There are more instances when we might need to actuate emergency stops (bikes and pedestrians popping out from behind other traffic, cars running red lights etc) and ABS would allow a safer and quicker stop?

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My only experience with ABS bikes was with a Versys I rented last year for a month. Wanted to check it out - think of buying one.

Between Pai and MHS was coming around a sharp LH corner. All good. At the apex some sand was spread across the road.

The abs caught it during trail braking and the front end did not wash out and allow a low-sider.

Happened so fast I do not know if I would have caught it. Visibility around the corner was not good.

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When I got my GS I played around with ABS on and off. As I learned where the edge was with ABS off, at low speeds, I noticed that I was stopping in a shorter distance than with ABS on and activated. The difference at low speed is small; a few off/on cycles at between 15 and 40 km/h results in an inch or two max. Since then I have mainly ridden on road and up country with ABS on and I am sure I have forgotten where the edge is. I think Mania is spot on on feeling brakes; once ABS activates, I might as well be driving a one of my Landys...

I think some more precise language is needed to describe ABS. In any situation where a rider brakes hard enough to activate ABS, a skid would have occurred were ABS not available. That alone will effect better stopping with ABS, as the skid and recovery (if any) will lengthen the stopping distance. And as you all know, at high speeds, or in a corner, locking a wheel, especially the front might end in an accident. IMO, this will be a major contributor to the percentage decrease in fatal accidents cited from some report in an earlier post...

In situations where the rider hits the maximum braking without activating ABS, they will achieve the best braking distance, however, if ABS is activated, the off/on cycle will add a small distance to the total braking distance for each cycle it performs. I have tested this myself, and at least with me, on my bike, I can repeat this consistently. If I keep the same pressure on the calipers once ABS is actuated, I can hear the wheels start to slide on gravel or sand, but there is no significant locking and braking is good. If I reduce pressure until the ABS is deactivated, braking is now smoother and according to my totally unscientific measurements, slightly more effective.

If you activate ABS by braking too hard you and don't reduce pressure to get to the point that ABS deactivates, you will add a few inches to your stopping distance. That is why I often turn it off in heavy traffic. ABS is great for many reasons, but it is not a guarantee of the shortest stopping distance in all situations - especially if you rely on it from beginning to end of a braking manoeuvre. I think it is a dangerous mistake to consider ABS as a fool-proof solution to braking, and I would encourage people to test it as I did (or better - not hard to) if they can.

As an aside, I did the basic course with Off-Road Skills here in Thailand and after body position the first thing we were taught was sliding the back wheel at speed, followed by controlling a front wheel slide. With the front brake loaded, in 1st gear and half-clutch, slowly accelerate while increasing braking pressure until the front wheel locks up - try and keep vertical for as long as possible, releasing the brake when you pucker up a little too tightly. It takes a while, but eventually most students can manage close to 10 meters in a front-wheel skid. I now ride off-road with ABS off most of the time...

Ride safe...

I noticed in the part I highlighted that you did the test on loose conditions. Isn't that the reason that dual sports widely have defeat-able ABS? For when you want the sand or gravel to build up in front of the tyre?

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Dave mate, I did the test on a loose surface as it makes it easier to get ABS to activate without scaring the living poop out of me! As for building up sand/gravel in front of the front tyre - never heard of that. Si Pavey taught us to get the front wheel up on the surface as soon as possible and keep it there. Initiate braking by accelerating hard to slip the rear wheel, then apply brakes. Counter-intuitive, but I was taught the same in 4x4, although I've not practised enough to say if it works for me - my ability to execute what I am taught is the issue... I may go practise sand in Rayong when I pass through on my border ride (currently paused...)

I noticed in the part I highlighted that you did the test on loose conditions. Isn't that the reason that dual sports widely have defeat-able ABS? For when you want the sand or gravel to build up in front of the tyre?

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Dave mate, I did the test on a loose surface as it makes it easier to get ABS to activate without scaring the living poop out of me! As for building up sand/gravel in front of the front tyre - never heard of that. Si Pavey taught us to get the front wheel up on the surface as soon as possible and keep it there. Initiate braking by accelerating hard to slip the rear wheel, then apply brakes. Counter-intuitive, but I was taught the same in 4x4, although I've not practised enough to say if it works for me - my ability to execute what I am taught is the issue... I may go practise sand in Rayong when I pass through on my border ride (currently paused...)

I noticed in the part I highlighted that you did the test on loose conditions. Isn't that the reason that dual sports widely have defeat-able ABS? For when you want the sand or gravel to build up in front of the tyre?

The build up method was what was taught to me for (non-motorcycle) off road riding.

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  • 2 weeks later...

When I had stock Dunlops D222 on my CB500F the ABS was activating almost all the time (specially after 6000 KM on them)

every time on the rear and on the front most of the time it was activated.

Once I changed tires to Pirelli Rosso 2, ABS has never activated even once, already 2000 KM riding on them.

So, Good tires and good braking technique is very important, I learned to squeeze the brakes and start applying braking much early. This reduced ABS activation a bit on old tires.

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Yes brake fluid is NOT incompressible. No liquid is ever incompressible, except in solid state.

However the compressibility coefficient is so low that is hardly matter, only when there is high humidity on the fluid, and temperature is above 200C. This is also very minimal, 0.003 MPa-1

Read: https://books.google.co.th/books?id=6TA3AAAAQBAJ&pg=PA186&lpg=PA186&dq=brake+fluid+compressibility+coefficient&source=bl&ots=ro7UogwGTB&sig=rDHl3CU7O5NOycBH5FX_T_kpiLs&hl=en&sa=X&ei=-pb5VN3sJJSVuASCh4Bg&ved=0CCMQ6AEwAQ#v=onepage

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