ABS vs. Non-ABS

[ewhite]

Just got a R1100S a few months back. I saw that A and S Bmw had the 5.5 rear wheels for ABS and w/o.

http://www.ascycles.com/detail.aspx?ID=1256

http://www.ascycles.com/detail.aspx?ID=1257

I was wondering if ya'll could tell me the difference was between the wheels of ABS equiped bikes and those without.

Thanks!

[Xa3]

The wheel for ABS comes with special round attachment that connects to hub that has many cuts in it for the laser sensor to monitor the wheel revolution. If the laser sensor notices that the wheel stops while applying brakes, it will "let go".

The wheel for without ABS comes without that attachment.

-ChaZ

[ewhite]

Could one fab an attachment for the sensor?

[jclark]

The wheels are cast differnt.

And just to be persntckety, it's not a laser doo-dah, it's just a magnetic field that is being disturbed by the 'cuts' as they go by ( count the pulses! )... the 'puter just counts them, and makes braking decisions based on how fast it thinks the wheel is going, combined with other inputs.....

jeff
...lets the 'puter count for him...

[RoundelRider]

Originally posted by jclark
The wheels are cast differnt.

And just to be persntckety, it's not a laser doo-dah, it's just a magnetic field that is being disturbed by the 'cuts' as they go by ( count the pulses! )... the 'puter just counts them, and makes braking decisions based on how fast it thinks the wheel is going, combined with other inputs.....

jeff
...lets the 'puter count for him...

Its a hall effect sensor, it produces a voltage as the metal sections of the ring pass by the sensor. when it quits generating a pulse (not sending any voltage to the ABS control unit) the ABS quickly releases pressure/allows pressure to reapply (through you applying the brake) from the brake circuit of that wheel until it starts to revolve again without locking up.

Im sure theres something specific to BMW that Im missing.

Can anyone tell me if "kickback" or odd lever feel is going on while the ABS is doing its job? Ive locked them up on cars purposly, never have on a bike.

[bikerfish1100]

i feel some mild ABS action/pulsing at the wheels, but nothing at the lever.

[Xa3]

Originally posted by jclark
The wheels are cast differnt.

And just to be persntckety, it's not a laser doo-dah, it's just a magnetic field that is being disturbed by the 'cuts' as they go by ( count the pulses! )... the 'puter just counts them, and makes braking decisions based on how fast it thinks the wheel is going, combined with other inputs.....

jeff
...lets the 'puter count for him...

Ah... I stand corrected.

-ChaZ

[jclark]

Originally posted by RoundelRider
Its a hall effect sensor, it produces a voltage as the metal sections of the ring pass by the sensor. when it quits generating a pulse (not sending any voltage to the ABS control unit) the ABS quickly releases pressure/allows pressure to reapply (through you applying the brake) from the brake circuit of that wheel until it starts to revolve again without locking up.

Im sure theres something specific to BMW that Im missing.

Can anyone tell me if "kickback" or odd lever feel is going on while the ABS is doing its job? Ive locked them up on cars purposly, never have on a bike.

>Ah... I stand corrected. :)
>
>-ChaZ

Me too! :)

On ABS II ( 99 S ), I have never felt anything at the lever. Just feels like suddenly yer plowing through molases...

jeff