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Interesting article on motocycling

Discussion in 'General Motorcycling Discussion' at netrider.net.au started by Ghibli, Aug 3, 2007.

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  2. Good article and thought provoking.

    I for one would certainly consider paying for “switchable†ABS and possibly traction control as they sound like sensible things to have off the track or in the wet (ie. When you don’t want to push the bike too hard).

    Anti-lock brakes seem to be a good idea, but traction control I’m not to sure of once off a straight line. What do the experienced riders think?

    Part of me still thinks it’s good not to have some of these electronic assistants in bikes as it seems to have taken the skill, and therefore the caution, out of cage dwelling…. If I have to be wary of what my bike will do on the next corner/road surface, then I’ll always ride with a healthy respect for it and it’s (and mine) capabilities.
    :)
     
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  3. After waiting for a week for the local Suzuki dealer to read a fault code on my Suzuki, I am not sure that I want any further complexity on a bike!.

    Cant fix electronics on the side of the road, under a streetlight, in the rain.
     
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  4. Weeeellllll gooooolllyyyyyyy, what we all are needin' is someone to be explaining all 'o this technomological doohickery to us dumbass motorsickle riders! :roll:

    I'm sure that once the technology is mature enough, and safe enough bike manufacturers will start fitting it. I know that there's some bikes fitted with ABS, but it would want to be a lot more sophisticated than the "lock - unlock - lock - unlock" systems used on most cars. And would anyone want the traction control suddenly cutting power mid corner because it's detected some loss of traction? Didn't think so.

    Yer average bike doesn't cost as much as yer average house either. :grin:
     
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  5. That's bona-fide class-A bullshit they're spinning there. The guys on Fifth gear say just exactly that every second time they drive one. 'Boring' is the word they use, and they keep looking for the switch to 'turn the bloody thing off.'
    traction control = anti-hooning device more like it. F1 cars have all that rubbish, and they are bloody boring.

    Scheff
     
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  6. lol tracktion control means no moe power slides, sudden loss of power when taking of from the lights and other weird shit.
     
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  7. now you're spinning some class A BS there mate - all those things have precisely NO bearing when it comes to driving on the road. Track yes, they might have a point. Road, regardless of situation, if you are running hard enough to invoke a slide you deserve a reckless driving ticket. I am also well and truely fed up with the drifters on many of the good roads around sydney, and also you fools who don't know that pulling the damn fuse for the abs will disable it if you need it temporarily like a track day or descending a muddy of loose rocky track (which i'm sure you lot do regularly!)
     
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  8. So do Superbikes. But after watching last night's races I doubt that you'd call them "boring".

    As for traction control, is there really a need for it on road bikes? Rear tyres are such that they can grip pretty well, even in the wet. For learner riders it might be an issue for wet weather riding, but they'd be on bikes that would be difficult to spin up the rear, anyway.

    There's also the issue of weight - how much would the bike versions of ESC, ABS and traction control add to the weight of a bike.

    BMW has ABS and any Beemer rider who has it swears by it.

    Then there's cost. Given that bikes are sold in much smaller numbers, economies of scale dictate that it would be more expensive, per unit, than a car's equivalent.

    Finally, how would traction control or ESC work in the real world? What would it do if you're cranked over in a corner and the rear end starts sliding. Will it detect the sideways motion? Does the rear start to spin up? If so, is it enough to be detected and to apply countermeasures?

    I wouldn't go poo-poo'ing it just yet. It might turn out to be A Real Good Thing. Only issue is that it'd take years before the entire fleet will have it.
     
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  9. Maybe. But they're doing this when they're drifting the latest sports car around a race track. Most cars are not driven like this, whether at track days or on the road. So really, what they're saying isn't relevant to the issue at hand - road safety for the masses.

    Really, how many of us can "back a bike" into a corner, power slide or whatever. I'd be tipping that it's bugger all. Johnny O is probably the only guy here who may be capable of this sort of thing. But does he practise this on the roads, or even on the track? Without knowing the guy I'd be tempted to say "no", regardless.
     
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  10. Four wheeled vehicles do not need to maintain balance, speed and lean angle while travelling around a corner of a particular, or varying radius. Motorcycles do. Anything that upsets the balance we all establish on every corner has to be a bad thing.

    My experience with ABS has all been bad, even in my current Lexus, which should have a good ABS system. Every time I have really needed to stop hard in an ABS fitted car, and the ABS has kicked in, it has scared the fricken shit out of me, and has done nothing to help in the situation. To be fair, it meant I could steer away from the rear of a car on one particularly greasy road, itstead of running into the back of it. But it also massively increased my stopping distance, so that I had to steer around the car in front. Of course, in doing so I took a big risk, because I had very little time to check noone was in the lane I was steering in to, or worse, sliding past me in that lane.

    One worse than that, ABS actually caused me to hit a car once. Crossing a wet road with tram tracks in both directions (four rails), traffic stopped suddenly across the intersection, when a driver got a fright from a truck next to her. I braked firmly and could have easily stopped, even in the wet, except that each time my wheels hit a wet tram track, ABS turned the brakes off. With the tram tracks also being a bit uneven, I had no braking at all, and slid across the road into the back of a car. I was just praying for the brakes to lock up a allow me to stop, but no, ABS did what it was designed to do, and I needed a new bumper. :evil:

    Let's also look at that statement from Germany, "showed most single-vehicle motorcycle crashes could have been prevented by anti-lock brakes or traction control because riders often overreacted in an emergency". Well, most single vehicle accidents I hear about involve a rider going into a corner too hard, panicing, standing the bike up, braking as hard as possible, and running off the road. How would ABS help in that situation? The solution to those situations is to turn in harder, not stand the bike up and brake. ABS might help in a straight line, on a wet or slippery road, say when traffic ahead stopped suddenly, but only if it was dual channel, and reduced the braking force rather than turning the brakes off-on-off-on-off. Otherwise, if you are already pulling a stoppie trying to avoid the rear of a car, and your rear wheel stopped turning, so the ABS kicked in, the brakes would go off on the front wheel, and you would roll into the back of the car in front. In that situation it wouldn't be a single vehicle accident anyway, as you ran into the back of a car. So in what kind of single vehicle accidents would ABS or TC or ESC help a rider?

    Remember, TC and ESC in a car involves applying braking force to individual wheels, or adjustments to the throttle, timing, etc. to prevent the loss of traction and steering. How does that apply to a motorcycle? The only situation I can imagine is to prevent rear wheel spin through a heavy hand on the throttle. Of course, if you are Johnny O and are doing a power slide through a corner, then that might be a bad thing. :p

    I would love to have a performance car with full TC, EBD, ESC, and a quality ABS system. Anything less that that, I think I can do without.
     
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  11. I might suggest that those of you translating car technology to a bike abs system (that they've no experience of) actually go and try one. You'll find that the current crop are not on/off like the old (and some new) car systems at all. They are more accurately described as antilock sensing brake systems and don't give the judder that has been seen in the past.

    ps for roderick - Please outline the reasoning behind knowing that you could have stopped faster without ABS on a road that you acknowledge was rather greasy and you were "scared ... of it"? Did you go back immediately having pulled out the ABS fuse and gave it another shot?

    Ii've had no problems in 'just rained a light mist in melbourne on the tram intersections around st kilda road and fitzroy streets in a '96 ABS equipped camry with worn shocks - wtf were you doing that resulted in you skipping over a stack of rails? Or were you braking along a set of rails, which would indeed be much more slippery than the asphault, but a locked wheel wouldn't have made a bleedin difference? Have you ever contemplated using the handbrake as well? No-one who designs these things has ever said that an ABS system allows a vehicle to stop in a shorter distance than a non ABS vehicle. What they are used for is to allow you to steer under maximum braking effort (as you found yourself) and cover for other factors such as training, tiredness, rapid changes in surface friction and most particularly for a rider, maintain vertical stability by stopping you lowsiding yourself with the front brake. There will also be a marked number of motorcycle incidents arising from people grabbing a front brake mid corner and lowsiding instead of just trying to make the corner - abs could have an impact here, however ABS will not save you if you are stupid. Likewise, you can't stop faster with the rear wheel off the deck compared to the back wheel skimming the blacktop with no load on it and this condition does not result in a drop in front brake pressure - you really ought to go and sample the current crop before mouthing off about them.
     
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  12. Well. I read your posts in the other thread on this article Bonox, and I was going to reference my post here, but I see you found it. First off, your repies here and in the other thread have been quite condescending, which is very unnecessary, so please stop that.
    Fair point, I haven't tried a bike with ABS. But as a Mechanical Engineer, I believe my experience of ABS on cars does translate quite well, so I'll stick by what I said. If ABS legislation specified the standard of ABS to be fitted, and how it would work, then it may be acceptable. But as even you noted, some new cars still have off-on-off-on ABS systems, and they would be completely unacceptable on a bike, as would a single channel ABS system.

    I know I could have stopped in a shorter distance because I am an experienced driver. The incident in question was on a left hand curve of a road that dropped away around the corner, reducing load on the tyres. At the same time the greasy patch was on the corner caused by cars braking in dry weather for the right hand turn from the right lane coming up. The whole road wasn't greasy, just the braking area. In the same way that stopping on gravel is better without ABS than with it, because a mound of earth forms in front of the tyres, assisting in stopping the vehicle, on a road which has one greasy patch, followed by simply a wet road, a locked wheel can wipe off the grease and gain better traction between road and rubber. In addition the effect of heating in a locked tyre improves traction. In the particular car I was talking about, a 1994 Mitsubishi Galant V6 24Value hatchback, the ABS system was an off-on-off-on system, and once activated, it tended to self perpetuate the need for ABS, as the brakes coming back on created such a shock that the tyres again lost traction. I think it was a single channel ABS system, which didn't help. The only way to regain braking without the ABS kicking in was to stop braking all together, then reapply the brake gradually. The Galant didn't have a bad ABS system, it was just an average system, much like many still being fitted today.

    Now you see what I mean by condescending? It was a 1994 Galant, as I said above. That car was fully japanese built, with a very advanced engine and excellent suspension, all in excellent condition. I was travelling south on Boldrewood Pde/Albert St in Preston, crossing Preston Rd, which has the tram tracks, so I was crossing the tracks at 90°. The road is slightly downhill, and the tracks are level, so that means path I had to travel was sloped-flat-sloped-flat-sloped. These bumps contributed to the ABS cutting in. I was a good three car lengths behind the car I hit, and was travelling at 60Kph. If the ABS had never cut in, and the tyres skidded across the tram tracks, I would have stopped with plenty of clearance. As it was, I didn't hit that hard, didn't visibly damaged the other car, but as I hit the corner of my bumber, it broke. As for using the hand brake. Well, hand brakes both tend to provide very little actual braking power, and if they do lock the wheel because the wheel is momentarily locked by the main brakes, they can be very hard to disengage quickly, which can result in steering issues. Handbrakes are great for assisting in turns on gravel or in slippery conditions, and for holding a car stationary, but not slowing a moving car.

    I'm glad you've had no problems with your poorly maintained '96 Camry. Perhaps you have never been in a situation that activated ABS? I hope you never do have such a situation. I only had two situations in that car where the ABS created a worse situation than if it didn't have ABS. While it activated more often than that, it was just annoying, and added no value, on other occassions. I never had a situation where I was glad of having ABS. No, I couldn't pull the fuse, as it didn't have an independent fuse, and any other means of disabling it caused electronic problems.

    Actually, yes, they do. Some claim all sorts of test results to prove it, but wont share all test methodologies or conditions, or put the results in context.

    On top of that, it is actually true that a excellent ABS system will stop a car faster than any human being can hope to achieve. In order to do that though, it needs to be a multi-channel ABS system, with proper sensors on each wheel, and the electronics to back this up. These systems apply progressive braking power, and are often combined with braking power assistance functions. They never allow any wheel to actually stop, unlike cheaper off-on-off-on systems. Under these circumstances, the electronics can apply the maximum braking force possible without locking up a wheel, which even an expert driver would have trouble with.

    The problem is, most ABS systems do not live up to this standard, and any legislation that requred ABS is unlikely to specify this standard as a requirement.

    Correct. Well, maximum braking in theory. ABS systems are a good idea for poorly trained or inattentive drivers. They are there for Joe Average. Most motorcycle riders realise that they need to be better trained and more attentive than Joe Average if they wish to survive.

    ABS does maintain steering control, as shown in countless safety campaigns we pay for. But what are you going to do with that steering in traffic? Run into the guy in the lane next to you? I was lucky that I had a temporarily clear lane next to me when I needed it, just lucky.

    Now you lost me completely. ABS will not prevent a lowside in a corner. How on earth would it? You are on a lean in a corner and you think you are not going to make it, probably believing that the tyres are at their limit of traction, or you would just turn in harder, and you put the brakes on? Well, if you do you have already done the wrong thing, and probably wont make it through the corner. Okay, you can, and I do, use light braking through a corner sometimes, but never enough to activate an ABS system. I certainly don't want anything interfering with my brake control when I do this. How about some brake assist: Touch the brakes lightly in the corner and the electronics decide you need more. Splat!

    On slow corners people who grab the front brake might (probably will)drop the bike, paricularly in wet conditions. But that is hardly a life threatening situation, unless the vehicle behind you doesn't see you or is too close. This wont appear on the statistics that the government wants to improve. Would ABS help here? Probably not, as a low side involves a sideways slide of the tyre, and often the tyres hasn't actually stopped turning before this happens, so ABS would not have kicked in. A low side accurs when all the traction available in the tyre is exceeded, and the wheel slips away sideways.

    In straight line heavy braking which results in a low side, yes, ABS could help. I said as much in my post.

    Actually you achieve maximum braking force when both wheels are on the ground, and 60% brake force is through the front wheel, 40% through the rear wheel, or there abouts. If having the rear skimming the black top does not result in a drop in front brake pressure, then the ABS has done nothing, so what good is it?

    If you read what I wrote about doing a stoppie, you'll see that my scenario still applies. I have had to do one really serious emergency brake on my Ducati, which resulted in the rear wheel lifting enough to cause the rear brake to lock the wheel, and stall the engine. At no time however, did the front wheel stop rolling, as I was concentrating quite hard on preventing that from happening. How would ABS have helped me in that situation? If it was a single channel system with sensor on the rear wheel, it would have detected that the rear wheel had stopped turning, and would have turned off the brakes, meaning I would have come closer to hitting the Ute that pulled out in front of me. With sensor on the front wheel, it woud have done nothing. If it was a dual channel system, it may or may not have reduced the braking effort on the front wheel. Still closer to the ute. If it was a very sophisticated front/rear balanced braking system with ABS, it may have reduced the front braking enough to keep the rear wheel on the ground, but I'm not sure how it would know to do that. Differential wheel speed analysis would be possible, with sensors on both front and rear wheels. That would help me on a bike in straight line braking, at the cost of feel and control in all other situations.

    You are right, I should look into specific implementations of ABS on bikes to see if they meet my standards, but I think I made a fair comment on the subject at hand, rather than mouthing off. I would hope you could do the same.
     
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  13. I have a couple of friends, both engineers, one mech, the other elec. One rides a K1200 Beemer with ABS. The other's a R1150RT. Both swear by the ABS.

    The benefit of ABS on a bike would be to stop the dreaded rear wheel lockup under heavy braking and the tank slappers that these invariably cause. It also stops you sliding down the road when the front locks up.

    I'm not sure what advantage ABS would provide, say braking mid-corner. These guys seem to think that it's a non-issue.

    Traction control would help stop the high sides that occur when the rear steps out and then grips. Classic is when tyres are cold, or when the rider guns it a bit with a new rear tyre on. Or, coming around a corner and you accidentally gas it up a bit too much.

    TC on my SS worked to make the engine miss and to push back on the throttle. It was switchable. So, if I wanted a bit of fun away from prying eyes I could do so.

    I Personally fully advocate the current crop of secondary safety technology that is being applied to new cars. It would be good to see a bike version of this technology. How it would be implemented, apart from ABS which is fairly obvious, I dunno.

    Finally, your experience with ABS (it alarming you), is common to those who've never experienced it. Most people tend to lift their feet off the pedal thinking that something's wrong, thus negating any benefits either braking itself or ABS has to offer.

    If you slam your foot hard on the pedal, the electronics will do the work for you. Thing is, you'd be doing the same on a non-ABS vehicle anyway and with the expected results.
     
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  14. I was going to reply, but RoderickGI has said what I wanted to say. I worked for BMW motorcyles back in the day (late 90s) and their various attempts at linked brakes and ABS at that time were inferior to a normal brake system in the hands of a capable rider, while representing a nightmare of plumbing and service costs.

    Perhaps in the future a bike version of ABS or even traction control can work. But to suppose systems fitted to cars (that operate in one plane) for use by pedal-stomping housewives, teenagers and executives, can work on bikes, is ludicrous. As always, bikers are mere statistics and we get no credit for the fact that your average motorcycle rider is vastly more skilled than his/her car-bound counterpart. If car drivers had our skill at throttle control and manipulating brake pressure, ABS would still be in the future for cars.
     
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  15. Bonox, i'll happily leave the rear spinning thanks mate.
    Traction control will no doubt end up safer for the majority of road users,
    but there will always be those who'd rather use the throttle to decide.
    Oh, and no i don't do drifting, this is a bike forum.

    The point i was making related to the statement "nobody says ferrari or porche with traction control are boring."
    Yes, they do. And they have since sold them.

    Scheff
     
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  16. Not wishing to sound full of myself but I know I can stop a car faster without abs than with. I know this because I did a bmw driver training course in 2002. Now I understand that these systems have come along way in this time but the point still stands. ABS is good for fools, and promotes the thinking: "It's ok! I'vve got abs, traction controll, Stability controll" what ever "new" safety measures that help people sleep is all well and good, but I'll take the man and machine with out the computers anytime.
     
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  17. A key point Roderick touched on (I told you he said it all but I'm gonna repeat it because I like the sound of my own posts) is that a major cause of bike accidents where the rider 'bottles out' are not due to failing to use all the braking force, but rather from failing to lean the bike as far as it can go. ABS and traction control will do nothing here and I suspect that account for a large proportion of the 'preventable' single vehicle accidents.

    Perhaps someone needs to do a study of the fate of riders who buy ABS and non-ABS Honda ST1100s or BMWs. But the only traffic studies ever done have to prove either the bleedin' obvious, or a tendentious point for the safetycrats.
     
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  18. Good points mjt57. As I said in my posts above, if ABS came up to my standards, I would be happy to use it. It's just that in my experience ABS hasn't come up to my standards.

    I've had the rear wheel hop about a bit under heavy braking, but never locked it up, except intentionally on gravel. I've never had the front lock up. I have had it hop as well, but that is a known issue for the Multistrada under certain conditions and settings. I don't think ABS would stop the hopping, front or rear, as that is the tyres losing traction, while the wheels are still spinning. It may help though, but would it increase my braking distance in doing so?

    The other thing is that I know my braking skills can improve, and that is part of the enjoyment of riding. If I had ABS, I would need less skill in braking, and would therefore enjoy riding less.

    Thanks for the positive feedback Heinz. :grin:
     
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  19. roderick - sorry for the delay in replying - new day and all.

    Your original post saying ABS stinks appeared to relate the poor qualities of a 1994 model system to a new lexus system; painting the world of progress with a very wide and tired brush. Yes, you have experience with a very old system and it had its failings - welcome to the big wide world. What I was trying to get across however, is that there has been significant progress in the world of sensor and actuator technology and the current systems that are available have none of the traits you would like to apply to them regardless of your engineering background.

    2channel systems? All bikes are two channel systems - as I wrote above, you have two wheel inputs and a static timer - there are no more inputs available. Are you thinking back to the three channel system on your galant that measured one (or an average of the two rear wheels) and each of the front wheels? - things have moved on)

    wheel off the ground statements - ignoring suspension compression for a moment, the mass height of the vehicle doesn't change under braking - if you can achieve 100% dynamic load on the front wheel, you will be braking at maximum capacity - doesn't matter about car distributions of 60/40 as you alluded - if you can put all the mass on one wheel, without raising the mass centre to encourage tip over, that is the best you can do. As the mass centre raises, you have to reduce braking pressure to keep the vehicle balanced - ask the guys doing balance point stoppies how much brake pressure they are using! Your impression that as soon as the rear leaves the ground, abs must kick in and reduce front brake pressure jumps to the wrong conclusion - yes, it may reduce front brake pressure, but the reason is just the same as a non abs system - you can't do more than increase your stopping distance if you let the back wheel off the ground.

    Finally, when you look at the technical documents from any ABS manufacturer/designer, they do not say outright that it will reduce your stopping distance compared to a vehicle without the system - you are applying perception and sales pitches to the problem and ignoring what I said. In fact all of the original ABS advertising from mercedes benz way back in the day only said it would allow you to steer around thing under maximum braking effort - nothing else. BMW's bike ads used to say it would stop you locking the front wheel and therefore dropping the bike in an emergency stop. If you want to read in joe bloe marketing company spin, go right ahead, but as a fellow engineer, I would hope you had more stones to think about the problem first.

    Also, regarding your rear ender, as an engineer analysing the incident a couple of things come to mind:
    1. the ABS system really did have a flaw in that circumstance (and i'm willing to bet that loophole has been closed when comparing to modern high rate computer power (or even between my old toyota and your older mitsubishi))
    2. your perception of what the vehicle was doing was tempered by other environmental factors (not least of which was the looming brake lights in front)
    3. you couldn't have actually braked any harder, and you are attributing poor driving forward planning resulting in a crash to the brakes. You can't magically get friction from nowhere and the wheels are released by the abs for a reason. This thread is also talking about mandating ABS on new vehicles, so the comments about >decade old technology is invalid here.

    As I said earlier, there is no point being a luddite and assuming that you are capable of outbraking technological advance - give the new set a shot and report back on the difference.

    Finally, there is at least one situation in which a computer reigns supreme for braking tasks: if friction levels (or loads - as in cornering) between wheels are different you can't stop one or two locked wheels and maintain maximum braking on the rest. This was the reason ABS was used in F1. Not because it was necessarily better than the (extraordinarily trained and talented) driver in all conditions but becuase it let you brake hard all the way to mid corner. And now we have come full circle as to the intent of antilock braking systems.
     
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  20. A poor workman blames his tools. He can also fail to utilise the tools at his disposal or he can become complacent - neither are mandatory. Practice with or without the tools is still required because of the many variables other than pulling the lever than go into controlling the machine. What kind of engineer are you anyway? Do you regard stressing as a pretty colour plot from nastran, or do you believe you still need a fundamental understanding of how the tool works in order to extract the most from it?
     
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