Welcome to Netrider ... Connecting Riders!

Interested in talking motorbikes with a terrific community of riders?
Signup (it's quick and free) to join the discussions and access the full suite of tools and information that Netrider has to offer.

ABS.... or not

Discussion in 'Bike Reviews, Questions and Suggestions' at netrider.net.au started by simon varley, Sep 25, 2008.

  1. I've done a quick search, and I can see that there are some of you guys who are pretty vehemently opposed to ABS on bikes. Is this based on personal experiences of moderns ABS systems, or just anecdotal or historic knowledge?

    I quite fancy a 650 Vstrom as the next bike and I can't make up my mind whether a $500 ABS system is going to be any good. Can I assume that no one here thinks ABS on a car is a bad thing? Clearly there are many differences between the two, but I wouldn't even consider buying a car these days if it didn't have ABS.

    So, on a bike, what's the issue? I know that in a car I've never had the ABS active on the road, but on the bike I've had the rear lock up a fair few times (TTR - knobbly tyres). Now ABS would prevent this, at least in a straight line, and improve stopping distances. Any argument on this?

    What's the issue on cornering? A correctly set up ABS system should sense the wheel just start to slip and correct this by adding brake. but only if you are already on the brakes surely? And the amount of additional brake the system has to add is minute and controlled, unlike the panic reaction of an unsuspecting rider who is just as likely to grap a fist or boot full and come off.

    I guess my questions sum up to:

    ABS - good or bad? and why
    $500 ABS - is a system this cheap likely to be any good, even if the concept is valid.

    over to you...............
  2. ABS (Anti-lock braking system) really only a bad thing if the vehicle operator uses it as an excuse not to drive/ride to the conditions, or relies on it to maintain vehicle control.

    Though for X-treme offroad situations and racetrack use, it would probably be better to turn it off or not have it equipped at all.

    If the rear tyre locked up because of brake operation, ABS would release the rear brake and reapply it.

    If the rear tyre locked up because of sloppy downshifting, no, ABS cannot help.

    ABS is not a magical physics-defying mechanism that magically halves stopping distances - all it does is release a skidding brake and reapply the brake quickly. The vehicle is still bound by the same laws of physics as everyone else, despite what all the car advertising implies.

    What it does do is gives the vehicle operator the confidence to fully apply the brakes with a reduced risk of a locked wheel causing them to lose control, rather than pussy-footing around at 30% or 50% braking effort. That is to say, ABS's goal is to give the operator the confidence to stop pretty much as fast as they can in those conditions.

    I think you have that bass ackwards, or are confusing ABS with stability control.

    If ABS detects a wheel skidding due to brake application (ie: wheel rotating slower than what the vehicle considers to be the road speed at the time), it releases the brake to recover the skid, then reapplies. Release, reapply, release, reapply, release, reapply.

    ABS doesn't add more brake, not even on cars.

    ABS is not stability control; it won't stop you from exceeding your vehicle's lateral grip, it won't keep the bike (or car) from spinning out due to sloppy riding/driving technique, etc. It releases a locked brake, nothing more.

    To the best of any of our knowledges, ABS is not capable of allowing a motorcycle to turn while emergency braking - not any more than a bike normally could, at any rate.

    Good if you want reassurance that in an emergency you can stop as hard as the conditions will allow (good for uncertain road surfaces, slippery conditions). Bad if you use it as an excuse to not learn proper emergency braking technique, don't leave a safe braking distance, etc.

    To reiterate - ABS vehicles are bound by the same laws of physics non-ABS vehicles do; the only thing they do is release the brake on a skidding wheel and quickly reapply it once the skid is recovered.
  3. I had a choice of ABS or not for about $450 and I went without as I'm not convinced it will benefit my style of riding.
    But I don't think we'll have much choice in a few years like carb v EFI it will become standard.
    A slipper clutch would have got my attention though.
  4. you're right of course. reading that back now I don't even know why I wrote that!

    so, in summary, ABS lets you use 100% braking capability with confidence. Emergency stopping distances are improved compared with brake/lock/release/reapply. This also applies to heavy (non emergency) braking if the rear is applied a bit hard.

    ABS operation should never be an issue in cornering as a) we don't brake IN the corner and b) even if we do, all that happens is any tyre slippage is prevented.

    right so far?

    so why are some people still so loudly against it?
  5. I have it and I hardly notice it.

    Once time it did come into play was when I was parking and failed to notice some gravel on the footpath and when I applied the brake the front wheel locked and the brake released.

    I over shot the parking spot but did manage to stay upright (whether or not it would have tipped over, no one knows).

    The other time was when a pedestrian popped out between parked cars whilst I was splitting. The added noise added to the "oh shit" factor for mr inattentive. ;)
  6. used it thismorning when an un-dodgeable kid on a pushy 4 times too big for him jumped out infront of me at an intersection.

    the front wheel ABS'd across a damp white turning arrow before normal braking ensued.
  7. Yepyep.

    If I can play Devil's Advocate for a moment;
    * More expensive
    * Most systems are more difficult to bleed than conventional brakes. More expensive to service, more things which can break.
    * There are situations where ABS has historically caused issues; early generations of car and bike ABS don't work so good on gravel/dirt.
    * There are situations where you may want total control over the locked/unlocked nature of the tyres, particularly in Xtreme offroading or in highly spirited riding (eg: racetrack).
    * Some ABS bikes can't/won't stoppie. ;)
    * Some people like the idea of being able to deliberately lay the bike down with a rear-brake lowside to avoid a crash. I've never quite figured that one out... :-k
    * Some people believe they can outbrake Rossi.
    * Some people prefer the technical purity of motorcycles; Rider aids dilute that purity. (As an owner of an old Toyota MR2, I can understand this)
    * By giving people a safety net, ABS may 'encourage' riders/drivers to never learn proper techniques because there's no obvious penalty for being sloppy. For example: Lock up the front wheel of a VTR250 and you go, "Oh fark!" and quickly release the front brake before the bike falls onto its side. You learn not to brake more smoothly and how to recover a skid. Lock up the front wheel of an ABS Tiger and you go, "Hmm, the brake lever's kicking. I must have engaged ABS. Ho-hum." - There's no real "carrot" to learn better technique because ABS mops up for you.

    As for me, well - I like my ABS Tiger. I still practice emergency maneuvers with it; besides skid-control, there's still "knowing" stopping distances (to be able to decide whether to brake or swerve), rider posture, being smooth+progressive...

    Ultimately... If you want the system, get it! If you don't want the system, don't get it. :)
  8. I have the DL650 ABS and because I have always been a bit heavy on the rear brake have noticed it coming on a few times, it works well.

    Never had the front ABS come on, so cant comment.

    As far as being a $500 unit, it is a Bosch and is apparently very good. The equal of any on the market.

    IMHO if it only saves you once, it'd be money well spent.
  9. I have a Bolwell 150 Euro and a K8 VSTROM, with some habits coming over from the former (ie trailing rear brake). Until you get used to the actual amount of brake pressure needed to slow/stop, the ABS does the trick like it or not. Does anyone know, at any particular time, the actual amoutn of brake pressure needed to sufficiently slow down? No. I'm not an extreme rider so ABS suits my style of riding ( I ride for rides sake!!) Again, if it saves you once a year............
  10. 2WA is right, of course, eventually it will be standard, like disc brakes themselves.

    And personally, if it saved me just once, even in the simple scenario that Vic described, I'd be thankful I'd opted for it.
  11. Maybe I'm misunderstanding what you mean by "learning the right amount of brake pressure", but...

    At the risk of sounding like a wanker, erm... Yes, actually, I would say that I do. New riders/drivers wouldn't initially, but over time you (should?) get a pretty accurate sense of exactly how much constant brake pressure to apply to stop on a specific point.

    Unless you meant, "Does anyone know how much brake they can apply at a given time without skidding the wheels?", in which case it can be a bit trickier... But I'd still answer "Yes, through a lot of braking practice." Except in the wet, but then, I bought an ABS bike to give me the confidence I to stop harder in the wet. I still leave the same "I can't stop quickly in the wet!" braking distance tho'.
  12. Hands up who has never locked a wheel and/or lost it and near on shit themselves as a result? Nobody knows exactly how much braking will be needed at any given event, not until you have gone past it will you know. Nothing counts more than experience yes, but has anyone experienced enough?!? And if over 90% of bike accidents are not at fault then what? Considering experience, riding style, conditions, wear and tear etc, anything that will help in the slightest is welcome in my book. ABS is not a placebo, it does have a function. Its in my tin top.
  13. One of the reasons I bought the Beemer was for the ABS option. I have to commute daily in heavy traffic in all weathers. Wet greasy roads with big white road markings, lots of impatient drivers and pedestrians with their heads down and add to that bad visibility. I can't say I've ever triggered the ABS and I'm always very careful but anything that may keep me upright if I do stuff up is ok by me.
  14. I've experienced front brake lockups on many occasion. And on many occasion the bike's gone down. I've been riding since 1973 so I've "grown up' with some pretty agricultural machinery, including an ag-bike as my first bike.

    the most recent incident was last November. I was about to turn into my driveway (right turn) when this person suddenly pulled away from the kerb and into my path. No indicators, no giving way to traffic already moving. I hit the picks, front locked up. Bike came to a halt at an angle that caused gravity to win over muscle.

    Blackbirds aren't light beasts and I couldn't hold it up. Result, one bent brake lever, one busted footpeg thingy that tells you when you're scraping it.

    ABS probably would've allowed me to straighten up as I came to a halt. But, having never ridden and ABS equipped bike and having never had that sort of situation on such a bike I can't say for sure. Still, it would be nice to have if it doesn't add too much weight to the bike, isn't loaded up with sensors that can fail and doesn't cost an arm and a leg.

    But then Honda, being what it is, would have some you beaut combined braking system linked to ABS, traction control and stability control with a lever poking out of the engine connected to a variable valve timing gear and another lever to turn it from a 200 valve engine to a 4 valve engine when you're in 2nd gear at 33.9km/h and on a lean angle of 13.44 degrees heading 267 degrees magnetic and a rabbit runs out in front of you...
  15. Totally Agree !!

    I've got it on my latest bike (FJR1300) and wouldn't be without it ever again. A measly $500 for something that can save your life ? I think you've answered your own question.
  16. ABS was activiated in my commodore a few times (when I had to stop very quickly.) I can feel the vibration on the brake pedal.

    Do you feel a vibration or something on either brake levers? I am thinking about getting a Suzuki SV650S, I think for a bit of extra money, I would get the ABS version.

    I would rely on normal riding judgement, procedures, etc. ABS is only for emergencies. I would still apply my brakes during an emergency the same way I was taught at a bike trianing course. ABS is designed to panic braking I think. It should not replace what you have learnt through training and practice.
  17. The short answer is 'yes', though the degree of pulsation varies from bike to bike.

    If the front wheel's ABS engages, the right hand's brake lever will begin to pulse. If the rear wheel's ABS engages, the foot brake's lever pulses. If they both activate, well, both pulse. :)
  18. I'm not a fan. I'm not as adamant as I used to be, because systems have got better. Reasons I am against it include:

    - Expence
    - Complication. This effects maintenance and reliability. I'm also a bit of a purists and believe bikes shouldn't have "gadgets".
    - Weight.
    - Of no benefit on the back brake
    - Very questionable safety benefits on a bike. This really is my main reason. Think about the way they work. They count on the brake being first locked, then release and repeating the process. Locking of front brakes should be discouraged, not encouraged, which is what an ABS system does. Even a small lock can cause disaster. Also they take away the feel of the front brake at the limit. Right at the time when you need it most. It's car technology that doesn't automatically convert to bikes due to the nature of bikes.

    As I noted at the beginning I'm not as adamant as I used to be, but I'm still very skeptical of any real benefit and a fair possibility of putting you in a worse situation.
  19. I've broken your post down a bit for ease of analysis.

    Then you go against all recent empirical quantitative and qualitative studies of motorbike ABS.

    - Expense: $500-1000 for safety is pretty minimal compared to other motorcycle gear. The beauty is that if you can't afford it you don't have to get it. Additionally when it becomes standard on Hondas for example, it'll become cheaper for everyone due to beneficial economies of scale.

    - Complication: ABS has safeguards built in to ensure correct operation. If it buggers up then you get a big warning light, and braking as normal ensues.

    - Back brake: it does benefit the rear. it will stop the back sliding out by preventing an initial major loss of traction could allow the wheel to move sideways under lock.

    - Safety benefits: Prefents you from overbraking. It doesn't stop you braking as normal and only comes in to help you when you've balls'd it up by locking a wheel.

    My experience of motorcycle ABS has been good. The feel is very much still there, although if I push a little harder (for whatever reason) I don't get a locked wheel but rather a smooth controlled stop.

    It hasnt 'automatically' been converted. Bike ABS senses and controls individual wheel rotation and loss of traction based on the torque of it's 2 wheels. Cars can have a variety of systems including ABS applied and/or sensed on all four wheels individually, together, or a combination of the two.

    Bike ABS was under development in the 80's so the iterations and refinements have been happening across the interim with a focus on development for bikes.

    Regardless, just like seatbelts, helmets, airbags and many other safety devices, ABS will continue to have its opponents for whatever reasons an individual can come up with. (however irrational they may be).

    The point of these devices is to target statistically significant sources of human injury/death and reduce the potential for disaster.

    I guess if you can outbrake a millisecond response computer controlled system in every situation, then ABS is not right for you. If you can't, then it's worth consideration and the choice comes down to the rider.

    In summary:
    It should be known and understood how ABS is beneficial and negative oppinions of it should be analysed and re-considered. The key is that if you don't want it then you don't have to get it. I'd just prefer people didn't spread negative oppinions that can misdirect others when those oppinions are not grounded in fact.
  20. Come on, Bazza from down the local doesn't count, nor does a BMW marketing brochure. I'm yet to see any real evidence they make motorcycling safer.

    You've pointed out one of my fears. We end up paying for a standard feature that we don't need but get because marketing has pushed it on us.

    Airbags in cars are a classic example of this. The chances of an individual being in an accident that needs an airbag are less than winning lotto. Yet we get them these days as a "free" feature in our cars. They are really just a way of getting more money out of us.

    The second thing that worries me about this mentality is the enforced ABS situation. Where some politician or someone senior in an insurance company decides they are a necessity.

    I was more thinking about the cost of repairs

    It's a pretty serious riding error that cause a back brake lock that big enough to cause an accident.

    No it doesn't. In fact it counts on the wheel locking for a period of time.

    I think your scale is out. ABS in the cars I've driven it allow the wheel to lock for quite a while before it releases pressure. It's probably only around half a second but certainly long enough to put a rider on his/her arse if it were the front wheel.

    I'm not trying to be rude, but I think you should check your "facts" a bit and be a bit more critical of their source.