sheridesabeemer
I Used to Be Someone
Smoothness was not my forte! That's why I'm signed up for track day this year!
When faced with a logging truck coming round the same switchback, ABS was a happy thing.
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How often does your ABS engage?
- Thread starter micstumpf
- Start date
Smoothness was not my forte! That's why I'm signed up for track day this year!
When faced with a logging truck coming round the same switchback, ABS was a happy thing.
ANDYVH
New member
I have had maybe one unintentional ABS event in 115,000 miles of riding.
I have had numerous intentional ABS events during practice of my high-energy stops. I regularly practice high energy stops to keep my skills sharp. Since I am an MSF instructor on occassion I have demonstrated ABS stops for my students.
Always keep in mind ABS is really only a stability aid, and that motorcycle ABS can do nothing for you if the bike is leaned over even slightly and the ABS is engaged. In fact, an ABS event while the bike is leaned over is likely to put you on your face.
All ABS systems work on a ratio of 20% wheel slip for a braked wheel near lockup.
So if the bike is leaned even slightly and the ABS engages during braking (doesn't this all sound wrong to you, cause it should) it will likely exceed the available traction and the bike can still go down.
Motorcycle ABS systems are intended to only be effective with the bike near vertical and braking in a straight line. You cannot create a motorcycle ABS event and steer/lean like you can a car.
I have had numerous intentional ABS events during practice of my high-energy stops. I regularly practice high energy stops to keep my skills sharp. Since I am an MSF instructor on occassion I have demonstrated ABS stops for my students.
Always keep in mind ABS is really only a stability aid, and that motorcycle ABS can do nothing for you if the bike is leaned over even slightly and the ABS is engaged. In fact, an ABS event while the bike is leaned over is likely to put you on your face.
All ABS systems work on a ratio of 20% wheel slip for a braked wheel near lockup.
So if the bike is leaned even slightly and the ABS engages during braking (doesn't this all sound wrong to you, cause it should) it will likely exceed the available traction and the bike can still go down.
Motorcycle ABS systems are intended to only be effective with the bike near vertical and braking in a straight line. You cannot create a motorcycle ABS event and steer/lean like you can a car.
jimvonbaden
Kool Aid Dispenser!
I think that is a bit of a stretch, like saying NEVER brake in a corner. ABS can and will work, as long as available traction is not exceeded! Same with braking in a curve!
Jim
ABS has saved me twice when a car in front of me stood on the brakes in heavy traffic on wet roads. The first time I was on a big wet plastic arrow, the second time I was riding over railroad tracks. ABS is worth the money.
Jay
ÔÇ£Once you can accept the Universe as matter expanding into 'nothing that is something', wearing stripes with plaid comes easyÔÇØ - Albert Einstein
Jay
ÔÇ£Once you can accept the Universe as matter expanding into 'nothing that is something', wearing stripes with plaid comes easyÔÇØ - Albert Einstein
ANDYVH
New member
ABS in a cycle is not like ABS on a car. Yes I agree to say "never" means it is all inclusive. But in this instance it is FAR safer to consider ABS as not intended for any leaning condition. And since cars do not lean and cannot tip over it is no big deal. But bikes have to lean and that eats a lot of traction. DO NOT ASSUME that ABS can and will function while leaning to any degree.
How do I know this? I worked closely on ABS systems with the Robert Bosch corporation, inlcuding test driving and development at Bosch's winter test facility in northern Sweden. I got to learn an awful lot about the funtioning of ABS systems, right down to studying the algorithms that determine the control by the computer. Car or bike ABS systems funtion very similarily in principle, but in actual use they vary dramatically.
Keep in mind, that leaning a motorcycle requires quite a lot of the available traction. NO motorcycle ABS system includes any kind of "lean angle" sensor to modify the ABS control if a brake were locked while the bike is leaned over. Note I said "brake is locked". ABS only engages once a wheel is locked. As anyone who has ever locked their front brake can attest, the loss of traction and stability is IMMEDIATE!
Since most of your traction is used for leaning when cornering, to apply the brakes in a manner to engage the ABS WILL use up ALL your available traction even if your have an ABS equipped bike.
I said it in my earlier post. ABS systems engage, during braking, when one or both wheels are "slipping" over the pavement at a speed 20% less than the actual vehicle speed. The 20% slip ratio was determined long ago to provide the best in vehicle stability and braking. But, this means the wheels have to slip that 20% in rotational speed before the ABS will engage. If you are leaning your bike through a turn, you DO NOT want ANY wheel slip because that means your have exceeded the available traction and you are likely to go down. If braking were engaged at this time, YOU ARE GOING DOWN.
Jim, in your response you state, "I think that is a bit of a stretch, like saying NEVER brake in a corner. ABS can and will work, as long as available traction is not exceeded! Same with braking in a curve!" Sorry but you are wrong here. For ABS to engage and do its' work, the available traction HAS TO BE EXCEEDED. That's the 20% slip I refer to. In a straight line, with no leaning, this is no problem. But leaning and an ABS event are not a good choice and the ABS CANNOT compensate for this. I don't mean to belabor this, but how can you make your statement will full certainty unless you have expereinced this yourself? I think you misunderstand the function of the ABS. ABS does nothing until a wheel is locked and potentially sliding.
I'm not saying this to belittle you or disrespect you, no way. I just want everyone to understand what your cycle ABS cannot do. If someone where leaning through a turn, saw an obstacle, and mashed the brakes on thinking the ABS will recover for them, it will not! Just because you have ABS on your bike does not mean you can apply the brakes while cornering any differently than if you did not have ABS. It is always up to the rider to manage the available traction and maintain stability. ABS will not do this for you in a turn.
So, in this instance, yes, it is proper to say braking should never be used in a manner that would engage the ABS while leaned to any degree. The ABS controller cannot adjust for the traction difference when leaned over, so it is far safer to assume the ABS cannot help when leaned over.
If you want to find out the hard way, I'd say "be my guest" but I would not wish the results on anyone. Just be aware what your ABS system CANNOT do and is not intended to do. I would love an opportunity to test this on an ABS equipped bike with outriggers (like BMW has) to show the difference. Plus I appreciate any other discussion or challenge on this.
How do I know this? I worked closely on ABS systems with the Robert Bosch corporation, inlcuding test driving and development at Bosch's winter test facility in northern Sweden. I got to learn an awful lot about the funtioning of ABS systems, right down to studying the algorithms that determine the control by the computer. Car or bike ABS systems funtion very similarily in principle, but in actual use they vary dramatically.
Keep in mind, that leaning a motorcycle requires quite a lot of the available traction. NO motorcycle ABS system includes any kind of "lean angle" sensor to modify the ABS control if a brake were locked while the bike is leaned over. Note I said "brake is locked". ABS only engages once a wheel is locked. As anyone who has ever locked their front brake can attest, the loss of traction and stability is IMMEDIATE!
Since most of your traction is used for leaning when cornering, to apply the brakes in a manner to engage the ABS WILL use up ALL your available traction even if your have an ABS equipped bike.
I said it in my earlier post. ABS systems engage, during braking, when one or both wheels are "slipping" over the pavement at a speed 20% less than the actual vehicle speed. The 20% slip ratio was determined long ago to provide the best in vehicle stability and braking. But, this means the wheels have to slip that 20% in rotational speed before the ABS will engage. If you are leaning your bike through a turn, you DO NOT want ANY wheel slip because that means your have exceeded the available traction and you are likely to go down. If braking were engaged at this time, YOU ARE GOING DOWN.
Jim, in your response you state, "I think that is a bit of a stretch, like saying NEVER brake in a corner. ABS can and will work, as long as available traction is not exceeded! Same with braking in a curve!" Sorry but you are wrong here. For ABS to engage and do its' work, the available traction HAS TO BE EXCEEDED. That's the 20% slip I refer to. In a straight line, with no leaning, this is no problem. But leaning and an ABS event are not a good choice and the ABS CANNOT compensate for this. I don't mean to belabor this, but how can you make your statement will full certainty unless you have expereinced this yourself? I think you misunderstand the function of the ABS. ABS does nothing until a wheel is locked and potentially sliding.
I'm not saying this to belittle you or disrespect you, no way. I just want everyone to understand what your cycle ABS cannot do. If someone where leaning through a turn, saw an obstacle, and mashed the brakes on thinking the ABS will recover for them, it will not! Just because you have ABS on your bike does not mean you can apply the brakes while cornering any differently than if you did not have ABS. It is always up to the rider to manage the available traction and maintain stability. ABS will not do this for you in a turn.
So, in this instance, yes, it is proper to say braking should never be used in a manner that would engage the ABS while leaned to any degree. The ABS controller cannot adjust for the traction difference when leaned over, so it is far safer to assume the ABS cannot help when leaned over.
If you want to find out the hard way, I'd say "be my guest" but I would not wish the results on anyone. Just be aware what your ABS system CANNOT do and is not intended to do. I would love an opportunity to test this on an ABS equipped bike with outriggers (like BMW has) to show the difference. Plus I appreciate any other discussion or challenge on this.
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jimvonbaden
Kool Aid Dispenser!
I'm sorry, I do not believe you, or on your absolute terms. I have braked quite hard in a corner, never engaging ABS. I have engaged ABS while at a slight lean turning into a parking lot on ice, and NOT fallen. ABS did its job.
My point is that there are no absolutes. Most MSF instructors will claim you should NEVER brake in a corner, and it makes their riders extremely scared of it, and makes them less safe.
I understand you have to make them understand the idea of limited traction, and limited availability of brakes in a corner, but to say never brake in a corner is doing a grave disservice to a new rider. It took me months to convince my GF that properly done you CAN brake in a corner. It may not be the best technique for riding, but CAN save your butt in an unexpected situation.
I believe the same applies to ABS. Do NOT count on it in a corner, but it is there, and can help you!
Believe what you like, and I will do the same.
Cheers.
Jim
My point is that there are no absolutes. Most MSF instructors will claim you should NEVER brake in a corner, and it makes their riders extremely scared of it, and makes them less safe.
I understand you have to make them understand the idea of limited traction, and limited availability of brakes in a corner, but to say never brake in a corner is doing a grave disservice to a new rider. It took me months to convince my GF that properly done you CAN brake in a corner. It may not be the best technique for riding, but CAN save your butt in an unexpected situation.
I believe the same applies to ABS. Do NOT count on it in a corner, but it is there, and can help you!
Believe what you like, and I will do the same.
Cheers.
Jim
knary
looking for a coal mine
A few scenarios:
1. hitting deer on day 4 of owning my bike. When I hit the deer, the ABS fired repeatedly. The front wheel stopped spinning for a moment.
2. Riding off pavement when I've forgetten to turn it off.
3. When coming to a stop here in the city on rough pavement. If you catch a tiny bit of air with the brakes on, the ABS will engage.
If you practice high speed stops and the ABS is engaging, you're using too much braking. You want to try to stop as fast and hard as you can without tripping the ABS. Use the ABS as a guide to help you find that line.
1. hitting deer on day 4 of owning my bike. When I hit the deer, the ABS fired repeatedly. The front wheel stopped spinning for a moment.
2. Riding off pavement when I've forgetten to turn it off.
3. When coming to a stop here in the city on rough pavement. If you catch a tiny bit of air with the brakes on, the ABS will engage.
If you practice high speed stops and the ABS is engaging, you're using too much braking. You want to try to stop as fast and hard as you can without tripping the ABS. Use the ABS as a guide to help you find that line.
J
JWHITE518
Guest
I'm not sure if I understand the logic in that. If using the ABS helps you to stop faster, why wouldn't you want to engage it in an emergency? The track day braking drills I've done have always shown that the ABS bike stops in less distance.
knary
looking for a coal mine
ABS is not intended to help you stop faster (as opposed to the ill fated servo brakes). It's intended to prevent skidding, allowing you to maintain control of the vehicle when braking too hard for conditions. It does this by releasing the brakes when the wheel stops while the vehicle is moving. Each time it pulses, each time it removes braking pressure, it lengthens the stopping distance.
This doesn't mean that ABS isn't a good and potentially life saving feature on the bike. When traction is compromised, especially when you don't realize it, ABS can mean the difference between staying up right and falling down. But if you're regularly tripping the ABS when stopping, you should work on your braking skills.
Were you comparing otherwise identical bikes with identical riders? Weight transfer, tires, etc all play into how quickly a particular bike can come to a stop.
ANDYVH
New member
As a 14 MSF instructor I learned long ago that to teach in "absolutes" can quite often miss the point of specific skills and abilities that riders develop over time and experience. Also, as a 34 year rider I have learned that the majority of techniques and skills are guidelines we use and adjust to the circumstances. Motorcycling is anything but absolutes.
Yet, in this case, I feel more strongly because of the expectations that many riders, including many that don't have a good grasp of motorcycle dynamics, put in "faith" on something like an ABS system. Also, comments made on internet forums soon become gospel or fact because someone put it in print. With something like ABS engagement while in a turn, there are far too many variables to say it will work all the time and save you from whatever the circumstances are.
I do not argue your expereince. Your speed while entering a parking lot was probably fairly slow, and it is great that the ABS system helped you. A low traction event like ice could probably only be best handled with strong rider skills and the help of ABS. I myself had an experience in Dec (this is in Wisconsin) where I realized I was riding at 55mph on ice! I was able to bring the bike to a controlled stop, turn around, go home and get my pickup truck. At that time my ABS was not working so I can't say what would have happened, but the ABS probably would have helped.
I too use braking in a corner when it is right to do so. I limit teaching this to my MSF students for the BRC program, mostly because braking in a curve is a skill to be learned with experience and not something beginning riders can consistently learn. You have to realize, the BRC program is formatted for beginning riders with no experience. They have their hands full just getting through the basics. I have had students with years of riding struggle with braking in a curve.
Your ABS worked for you in the event you describe. But an ABS event at higher speeds in corners will have much different results. This is what I really caution, that ABS at lower speeds and ABS at higher speeds, both in corners have very different results. So it is not safe to say it is the same for all instances.
I'll leave it at this. Just keep in mind, whether straight up or leaning in a turn, ABS only becomes active when traction has already been exceeded. ABS does nothing until wheel slip is initiated WHILE braking. Just please be careful when braking in a curve, because if ABS is engaged your tire(s) are already slipping. Being that close to loosing traction and control while leaned over can lead to hurtful results. That is the main point of my tirade, take for what it is worth to you.
Yet, in this case, I feel more strongly because of the expectations that many riders, including many that don't have a good grasp of motorcycle dynamics, put in "faith" on something like an ABS system. Also, comments made on internet forums soon become gospel or fact because someone put it in print. With something like ABS engagement while in a turn, there are far too many variables to say it will work all the time and save you from whatever the circumstances are.
I do not argue your expereince. Your speed while entering a parking lot was probably fairly slow, and it is great that the ABS system helped you. A low traction event like ice could probably only be best handled with strong rider skills and the help of ABS. I myself had an experience in Dec (this is in Wisconsin) where I realized I was riding at 55mph on ice! I was able to bring the bike to a controlled stop, turn around, go home and get my pickup truck. At that time my ABS was not working so I can't say what would have happened, but the ABS probably would have helped.
I too use braking in a corner when it is right to do so. I limit teaching this to my MSF students for the BRC program, mostly because braking in a curve is a skill to be learned with experience and not something beginning riders can consistently learn. You have to realize, the BRC program is formatted for beginning riders with no experience. They have their hands full just getting through the basics. I have had students with years of riding struggle with braking in a curve.
Your ABS worked for you in the event you describe. But an ABS event at higher speeds in corners will have much different results. This is what I really caution, that ABS at lower speeds and ABS at higher speeds, both in corners have very different results. So it is not safe to say it is the same for all instances.
I'll leave it at this. Just keep in mind, whether straight up or leaning in a turn, ABS only becomes active when traction has already been exceeded. ABS does nothing until wheel slip is initiated WHILE braking. Just please be careful when braking in a curve, because if ABS is engaged your tire(s) are already slipping. Being that close to loosing traction and control while leaned over can lead to hurtful results. That is the main point of my tirade, take for what it is worth to you.
ABS question
I have been told by another rider that the ABS pump will pull down your battery in a short trip situation involving repeated restarts. I am toying with the idea of IF I want to spend $2000 more for a used R1150R with ABS or not. I've read several articles and am leaning towards it. Also, is there a significant amount of extra maintenance expense with ABS ? I have never had the experience of a bike with ABS( and don't know where I would or can) and have also been told that it is a love hate item-i.e., riders either swear by it or swear at it. Is there a larger issue of " my riding skills don't require it" because I can brake with more skill when in total control of the brakes w/o a computer doing my brake work? I ready for some more of your thoughts on this subject. The IBMWR web site has a 1992 test that looks at stopping distances on different surfaces and with various categories of riders-the figures are quite impressive with ABS working for you!
I have been told by another rider that the ABS pump will pull down your battery in a short trip situation involving repeated restarts. I am toying with the idea of IF I want to spend $2000 more for a used R1150R with ABS or not. I've read several articles and am leaning towards it. Also, is there a significant amount of extra maintenance expense with ABS ? I have never had the experience of a bike with ABS( and don't know where I would or can) and have also been told that it is a love hate item-i.e., riders either swear by it or swear at it. Is there a larger issue of " my riding skills don't require it" because I can brake with more skill when in total control of the brakes w/o a computer doing my brake work? I ready for some more of your thoughts on this subject. The IBMWR web site has a 1992 test that looks at stopping distances on different surfaces and with various categories of riders-the figures are quite impressive with ABS working for you!
ANDYVH
New member
Nope, no additional maintenance costs for the ABS equipped bike.
No, the ABS system does not "pull down the battery". I wonder how the other determined this? The ABS system only activates its confirmation test after the bike is running. So once the bike is running, the alternator provides all the juice the bike needs, the battery has nothing to do with it then, and neither doe the ABS. If the other rider thinks the ABS lights flashing alternately is a sign of the battery drawing down because of the ABS, he is mistaken. It is a case of the ABS computer sensing system voltage below its minimal thresehold. The ABS does not cause the battery to go down, it merely senses it is down.
But the ABS computer is sensitive to first start of the day cold weather starts. At first start of the day, if the battery is a bit low on capacity, the initial start up of the engine can cause a low-voltage "soft" failure of the ABS system. But once the bike is running and the ABS system senses proper voltage, everything is good. However, the "soft" system failure will only be cleared upon the next restart of the engine.
The ABS pump only first engages AFTER the bike is running and after it has attained about 3mph speed. Once it gets the speed signals from the wheel speed sensors, the ABS pump cycles as part of the initial start up test. After that it does next to nothing until an ABS braking event occurs.
No, the ABS system does not "pull down the battery". I wonder how the other determined this? The ABS system only activates its confirmation test after the bike is running. So once the bike is running, the alternator provides all the juice the bike needs, the battery has nothing to do with it then, and neither doe the ABS. If the other rider thinks the ABS lights flashing alternately is a sign of the battery drawing down because of the ABS, he is mistaken. It is a case of the ABS computer sensing system voltage below its minimal thresehold. The ABS does not cause the battery to go down, it merely senses it is down.
But the ABS computer is sensitive to first start of the day cold weather starts. At first start of the day, if the battery is a bit low on capacity, the initial start up of the engine can cause a low-voltage "soft" failure of the ABS system. But once the bike is running and the ABS system senses proper voltage, everything is good. However, the "soft" system failure will only be cleared upon the next restart of the engine.
The ABS pump only first engages AFTER the bike is running and after it has attained about 3mph speed. Once it gets the speed signals from the wheel speed sensors, the ABS pump cycles as part of the initial start up test. After that it does next to nothing until an ABS braking event occurs.
knary
looking for a coal mine
You can address the ABS-fault-on-startup with
http://www.ibmwr.org/r-tech/oilheads/ABS-II_low_voltage_modification/index.shtml
I have occasional days of very short trips around town. Works like a champ.
http://www.ibmwr.org/r-tech/oilheads/ABS-II_low_voltage_modification/index.shtml
I have occasional days of very short trips around town. Works like a champ.
knary
looking for a coal mine
The battery on my GS is so low these days that on cold days, the clock zeros out.
On those days, the ABS always faults on start up. At the next red light, I restart the bike and the ABS resets appropriately. Bad of me, I know.
S
SNOONE
Guest
I've tested the ABS on hard stops, but this morning in rush hour traffic on the helix leading to the Lincoln Tunnel I was totally careless and stupid.. I was screwing around with my zumo trying to get a new channel on xm when I looked up and SURPRISE. I squeezed the brakes for all they were worth and lo and behold I stopped as advertised without cracking my skull on the rear bumper of the car in front of me.. Needless to say I have learned a valuable lesson once again.
greenwald
New member
Used ABS Many Times!
In my last two years of duty as a police motor officer, the Harley-Davidson Road Kings I rode were equipped with anti-lock brakes. I taught a Skills Refresher Course each spring to area motor officers, and the braking exercises I set up employing ABS had impressive results.
Riding eight hours a day in city traffic on duty, my fellow motorists provided me with numerous opportunites to use ABS to prevent a collision, and I wouldn't ride without them (unless off-road).
When I bought my '05 R1200RT, it came standard with ABS. If it had been an option, I would have payed to have them.
Good Luck!
In my last two years of duty as a police motor officer, the Harley-Davidson Road Kings I rode were equipped with anti-lock brakes. I taught a Skills Refresher Course each spring to area motor officers, and the braking exercises I set up employing ABS had impressive results.
Riding eight hours a day in city traffic on duty, my fellow motorists provided me with numerous opportunites to use ABS to prevent a collision, and I wouldn't ride without them (unless off-road).
When I bought my '05 R1200RT, it came standard with ABS. If it had been an option, I would have payed to have them.
Good Luck!
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