Originally Posted by shokhead
I had a 99 trek 7500 and it had a abs type thing on the front brake so it would'nt lock up and it worked pretty good. Wonder why they dont use them more?
As I recall, Shimano produced two types of modulator devices. Neither of them perform like real ABS units which could detect wheel spin (or rather wheel lockup) and force a backoff or reintroduction of the braking effort as appropriate. The "inline" brake modulators were mainly attached to the cables on lower-end and hybrid bikes. They basically created a non-linear pull of the cables to prevent an initial grab (pull) on the brake levers from applying too much effort. The second form of brake modulator actually came first (introduced about 10 years or so ago) and was called (probably still is) "Servo-Wave". This mechanism was integral to the levers themselves and used a special ramp cutout to introduce a non-linear leverage on the cable end. They were also adjustable/tunable. These are still available on the high-end cable-actuating MTB levers I believe. They came in two forms (stepped and stepless). The higher end units were stepless.