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Old 14th March 2011, 14:04   #46
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Default Re: ABS for bikes: How different from cars?

I have Saferide on my TBTS. It is only a brake modulation/moderation device that serves to "soften" grabby brakes; it is not a true ABS. You can skid and fall during straight-line braking with Saferide, as I have, which you cannot with a true ABS. It also can be attached only to disc brakes.
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Old 14th March 2011, 15:48   #47
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Default Re: ABS for bikes: How different from cars?

Hi,
I thought we had closed the chapter on the 'Saferide ABS'. Let's not go off topic.

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Old 14th March 2011, 18:34   #48
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Default Re: ABS for bikes: How different from cars?

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Could you please elaborate on it. As in 'in this condition, I would brake like .... because the laws of physics say ......

The accepted practice on bikes is no braking while turning. Why?
Linearity is v.important in brake system design. You want intervention only during panic/lockup.
When a 2-wheeler is leaned over, the contact patch is diminished quite a bit. Plus I dont think ABS action during turning would hurt in anyway would it??
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Old 14th March 2011, 20:37   #49
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Default Re: ABS for bikes: How different from cars?

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Plus I dont think ABS action during turning would hurt in anyway would it??
Hi,
Far from ABS, would braking hurt in any way? I don't know. And till someone gives me a bike fitted with outriggers, I'm not about to try out.

Logically, a bit of braking and a bit of turning shouldn't hurt. Trick would be in quantifying 'bit'.

Did you take advanced riding courses? What did they teach there? And the rationale behind their advice?

Re: linearity: A truism. Any rider input should ave a linear input-output response. When they do, we call it a sweet machine, otherwise a dog. (Not getting into what is feedback now.)

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Old 14th March 2011, 20:51   #50
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Default Re: ABS for bikes: How different from cars?

braking in turn will not hurt as long as only rear is used .

btw do you ride a bike ? i think not
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Old 14th March 2011, 20:53   #51
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Default Re: ABS for bikes: How different from cars?

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Hi,
I thought we had closed the chapter on the 'Saferide ABS'. Let's not go off topic.

Regards
Sutripta
was just clarifying an honest doubt another poster had. I must say that your constant comments on other members' posts and attempts to make this thread discuss only what you want to discuss are beginning to get under my skin.

You are just the thread starter, not the thread owner. Lay off, buddy.

Last edited by Rollin' Thunda : 14th March 2011 at 20:54.
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Old 14th March 2011, 21:06   #52
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Default Re: ABS for bikes: How different from cars?

Hi,
Bikers sure are aggressive!

@Nobody: Would recreational riding count? If not, no.

@RT: I think someone should start a new thread on the Saferide system. Would be great. Otherwise, don't you think its OT?

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Old 14th March 2011, 21:50   #53
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Default Re: ABS for bikes: How different from cars?

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Hi,
Bikers sure are aggressive!

@RT: I think someone should start a new thread on the Saferide system. Would be great. Otherwise, don't you think its OT?

Regards
Sutripta
Not worth starting a thread on Saferide. However, as Saferide claims to be ABS, it is not OT to clarify that it is NOT so. And that is more convincing coming from people who have Saferide (as I do) than others who just read about it on the the internet.

Yes, Bikers are aggressive, otherwise they just get run over
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Old 14th March 2011, 22:24   #54
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Default Re: ABS for bikes: How different from cars?

Hi,
The other posters tone was that we are disregarding the saferide system because it is cheap. Do you think this can be answered properly?

Quote:
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Yes, Bikers are aggressive, otherwise they just get run over
Aggression prevents you from being run over! Live and let live!

BTW, I have a TBTS also. Very grabby front brakes.

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Sutripta
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Old 15th March 2011, 18:35   #55
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Default Re: ABS for bikes: How different from cars?

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H
Did you take advanced riding courses? What did they teach there? And the rationale behind their advice?
Nopes. But I've raced bikes in Sriperambudur (and crashed too..lowside). I still remember the pain...so now I always brake in a straight line.
Also fallen off my Kinetic Honda in the rain riding doubles.
Quote:
Originally Posted by Sutripta View Post
we call it a sweet machine, otherwise a dog. (Not getting into what is feedback now.)
For brakes, we call it either grabby, soggy or crappy/wooden depending on the response.

as far as the 'bit', it just comes from practice and feel. Its like teaching someone to drive for the first time. You tell them to release the clutch a 'bit' and you know what happens next.
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Old 15th March 2011, 20:51   #56
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Default Re: ABS for bikes: How different from cars?

^^^
The advantages of being in the South. (I believe Yamaha is going to hold rider training sessions again. Nothing in the East though.)

When we lock up, the wheel stops rotating (dw/dt=0).
When we come to an actual stop, the wheel also stops rotating.

In a bike, can we use the same strategies as in a car for differentiating between the two? Or what strategies should we use on a bike?

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Sutripta
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Old 16th March 2011, 17:37   #57
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Default Re: ABS for bikes: How different from cars?

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In a bike, can we use the same strategies as in a car for differentiating between the two? Or what strategies should we use on a bike?
Hmm....what strategy is used in cars? I suppose look at the other wheel. or look at -d/dt(dw/dt) which is the same as d^2w/dt^2.
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Old 16th March 2011, 21:41   #58
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Default Re: ABS for bikes: How different from cars?

Other than all the internal cross checks (rate of change etc) one always has three other wheels to compare against. Choose the one with the highest rpm as unlocked. If below a certain speed, disengage ABS.

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Old 16th March 2011, 21:50   #59
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Default Re: ABS for bikes: How different from cars?

The way ABS checks if lock-up is occuring is by keeping track of the difference between the rotational velocities w of the the two wheels. In straight rolling, there should be no difference; when one wheel locks up there will be considerable difference, then ABS releases the brake on the slower-moving wheel.

As a rider you obviously cannot do this. You have to learn to recognise the skidding sound which occurs when lock up occurs, and release the brake immediately.

The reason hard braking with the front brake is not recommended during turning is because it tends to de-stabilize the bike. The braking force from the front brake on a turn does not pass through the (horizontal plane projection of the) center-of-mass of the bike and rider, and thus tends to spin the bike around its vertical axis and de-stabilizing it, as Mpower learnt on the track. Braking with the rear does not have this problem, and just starightens the bike. But the rear-brake is not so powerful, so the best thing to do on a turn is to first straighten the bike (by using the rear brake and the steering) and then applying both brakes as normal, as Mpower said.

Last edited by Rollin' Thunda : 16th March 2011 at 22:02.
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Old 16th March 2011, 22:38   #60
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Default Re: ABS for bikes: How different from cars?

^^^
Hi,
In a bike, would the fact that one can compare one wheel only against one other, that too with its independent braking circuit, cause any problems?

In a car, if on a turn one applies the handbrake (operating on the rear wheels), one has, well, the handbrake turn. Certainly doesn't straighten out the car. Why the expected differences between car and bike?

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