Most people think that it is supposed to allow your vehicle to get as close as possible to a skid without actually doing a skid - that's all. As it turns out, that is not at all what an ABS system does. A very well trained biker can do what is called 'Threshold braking'. Again, assuming a roadway with a Static CoF of about 1.0, that means that this exceptionally skillful vehicle operator is able, without ABS, to achieve a deceleration rate somewhere between 0.8g's and 1.0g's WITHOUT LOCKING UP HIS BRAKES. Once he locks up a brake the bike begins to skid and will continue skidding because his deceleration rate is higher than the Dynamic CoF - at lest until he loses some of that deceleration rate. ABS is designed to do EXACTLY the same thing from a deceleration rate point of view, BUT it does this in a different way than does a human operator. The ABS reacts to a skid! That is, as soon as a tire is no longer spinning at the same speed as the bike is moving (difference between the rotational speed of both tires), or there is a noticeable (to the computer) abrupt spike in measured rotation of an individual wheel indicating a discontinuity, it RELEASES brake pressure to stop the skid, then it immediately reapplies that brake pressure - and it does it many times within a single second. What that means is that an ABS braked bike ACTUALLY SKIDS to a panic stop. It should, therefore, have a deceleration rate during that stop somewhere BETWEEN that of the Dynamic and Static CoF (0.8g's to 1.0g's). The slower reacting the ABS system is (number of pulses it can generate in any one second), the lower will be the average deceleration rate achieved. Older generation ABS systems could attain deceleration rates only slightly higher than the Dynamic Cof and left a DARKER skid mark as a result while newer generation ABS systems attain an average deceleration rate pretty close to the Static CoF and leave a lighter skid mark as a result. Expert threshold braking humans leave a very light skid mark when they brake.