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Thread: abs on a bike

  1. #1
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    abs on a bike

    i once saw abs rim brakes for a bike there was a roller behind the pad and somehow stopped the brake from locking,but what about discs do they do them.

  2. #2
    Pedaler of dirt
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    ABS is your index finger, modulation is the key.
    It's not enough that we do our best; sometimes we have to do what's required.

  3. #3
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    This is my safety...


  4. #4
    Bicyclochondriac.
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    Quote Originally Posted by rize5boyuk
    i once saw abs rim brakes for a bike there was a roller behind the pad and somehow stopped the brake from locking,but what about discs do they do them.

    Interesting. I have not heard of a working production model of ABS for disc or rim.

    My general take on MTB ABS is that it is unnecessary and kind of silly, however it is only a matter of time until someone develops and markets it and people start buying it.

  5. #5
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    It was an old rim brake system. Give me a minute... dammit, can't find it. I did find this, though.

    http://www.budbrake.com/faqs.html


  6. #6
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    yep a canti type with a roler behind it.

  7. #7
    Engineer The Future Now!
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    Quote Originally Posted by sanjuro
    This is my safety...

    hahaha "Hoot" was a badass
    holy...

  8. #8
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    found it....

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  10. #10
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    Quote Originally Posted by rize5boyuk
    found it....
    Thank you... that would have kept me up.

  11. #11
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    Brovedani CNC'd anti-lock canti's

  12. #12
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    I thought anti-lock brakes is for people who can't drive in snow.

  13. #13
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    abs is bad in snow,i turn my abs off its more fun

  14. #14
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    Grease your rotors, that will keep your wheels from locking up. Or at least that's what I hear in the beginner forum.

  15. #15
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    QUOTE=rize5boyuk]http://www.blackbirdsf.org/brake_obscura/mtb.html[/QUOTE]

    Problem w/those is they pulse the brakes all the time and they rely on the tire to keep rolling to make them pulse. I bet if you really grabbed a handful of brake you could still lock up the wheel (especially the rear) because you'd stop it before the roller could turn enough to pulse the brake off.
    What you want is for the brakes to pulse only when the tire locks up and stop pulsing if it gets enough traction to start turning again (if it keeps pulsing you lose braking power).
    For that you need an external power source to pulse the brakes (cars use a hydraulic pump and accumulator), sensors to detect wheel lock up (or an imminent trip over the bars due to too much front brake) and a controller to activate and deactivate the ABS. All this adds weight and cost.
    Interestingly though you could use ABS on the rear for traction control too - with the right sensors & programming you could get it to stop your rear tire from skidding out on a climb and keep your front tire down.
    Last edited by Surestick Malone; 04-21-2009 at 05:39 PM.

  16. #16
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    A mechanical ABS is the stupidest idea ever. ABS keeps you out of trouble b/c the computer can calculate when to let go and how much to let go. Even a wrong calculation can result in ABS that's no better than none at all. Read here to learn about how ABS works. http://www.stoptech.com/tech_info/wp...rakekits.shtml

  17. #17
    Happy in Happy Valley
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    All around bad idea.

    Honestly I don't even like em on my car... when the system fails bad things happen. I had an older Chevy blazer awhile back; the ABS speed sensors on one axle failed, making the computer think the wheels were locked... so the abs would engage to stop the 'skid' and triple or quadruple braking distance. I discovered this when I tried to stop behind a school bus one dry, sunny day... had to use the parking brake to stop the car. Scary.

    So not only do I consider them dangerous, the added complexity to implement them effectively on a bike would be insane. Those roller canti's are an interesting bit of history though.
    Rigid Surly 1x1 650b--------Fixed CrossCheck--------Surly Pacer-------Salsa Ala Carte

  18. #18
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    abs is good if used the right way,the trouble nowadays is the fact you cant turn it on and off.abs in todays cars is linked to the traction control and stability systems.and the on/off button on some cars dont really turn it off eg bmw or new vw`s.(there is a way to turn it off fully).
    i have a old audi 1990 and u can turn off the abs totally.if one sensor fails the whole lot turns off and a warning light shows.anyway back to the subject...mechanical abs system would be fine if u could turn it on and off as needed.

  19. #19
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    ABS as it relates to cars was only to make it to where the average unskilled driver could steer while braking hard. It absolutely does not shorten stopping distances on dry pavement over a skilled driver. I went out and proved this over and over in front of some friends in my '06 TL. I could knock off 10' from 60mph with the ABS fuse pulled. 10' is a lot when it comes to avoiding the car in front of you.

    Ever try to stop on a washboard gravel surface with anti-locks? The will quadruple your stopping distance. The only time I lilke them is when entering a corner too hard and the inside front tire will try to lock without ABS. Another is when one side of the car is on dry pavement and the other is on a wet section or dirty section. On snow and sometimes dirt you want the tires to lock to make a wedge of snow or dirt in front of the tire.

    Besides, aren't there times when you want to lock a tire on a mountain bike? I'm still a newb at this but sometimes I'll lock the rear on a very steep and slippery decent and use the front as needed.

  20. #20
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    Quote Originally Posted by BuickGN
    sometimes I'll lock the rear on a very steep and slippery decent and use the front as needed.
    Please don't do this! It causes trail erosion.
    Tires have more grip when they are rolling, not sliding, so you are actually reducing the amount of braking you have available by locking the rear.

    It's best to either roll the slope without brakes if you can then brake once the trail flattens out or brake without locking the rear.

  21. #21
    I Tried Them ALL... Moderator
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    ABS on a bike would weigh a ton. Its complete overkill, when your feathering index finger is all you need to have ABS-like stopping.
    "The mind will quit....well before the body does"

  22. #22
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    We have ABS on our rim brake shop bike, it's this wierd cam that both brake lines feed into and are then connected. You have to just pull the rear brake otherwise the front has too much lever travel, I guess it works. We just did it as a joke, I can't imagine riding for real with the damn thing. Haha.

  23. #23
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    Quote Originally Posted by Surestick Malone
    Please don't do this! It causes trail erosion.
    Tires have more grip when they are rolling, not sliding, so you are actually reducing the amount of braking you have available by locking the rear.

    It's best to either roll the slope without brakes if you can then brake once the trail flattens out or brake without locking the rear.

    Understood and good timing. I'm going on my first real trail this Sunday. So far I've been making my own trails so the erosion hasn't mattered to this point. You might have saved me from pissing people off. Thanks.

  24. #24
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    Quote Originally Posted by BuickGN
    Besides, aren't there times when you want to lock a tire on a mountain bike? I'm still a newb at this but sometimes I'll lock the rear on a very steep and slippery decent and use the front as needed.
    about the only time i want to lock is in a very sharp corner, even then it isn't useful. for steep descents, it is much easier to use the front and front only. that way, you can control any skid while retaining maximum power and stability. that changes when you have mud though

  25. #25
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    Quote Originally Posted by vk45de
    about the only time i want to lock is in a very sharp corner, even then it isn't useful. for steep descents, it is much easier to use the front and front only. that way, you can control any skid while retaining maximum power and stability. that changes when you have mud though
    On a really steep hill you have to be careful with the front brake, it's easier to go over the bars for the same reason it's easy to lock up the rear wheel - your weight (center of gravity) is over the front wheel.

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