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Old 11-07-08, 03:53 PM
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DannoXYZ 
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Originally Posted by vrkelley
What's the skin-nee on the disk brakes? We know they're not anti-lock like car brakes. But do they prevent endovers (flying over the handlebars if you brake with the front brake before the back)? Less skidding on wet pavement?
Just a clarification, the "flying over the bars" sensation is based upon Newton's laws. What's actually happening is that the braking/deceleration force is pushing back on the bike at the front-tyre's contact patch. The body on top still wants to continue in a straight line at the same speed as before. You end up with a torque around the front contact patch.

This torque has ONLY to do with the amount of deceleration, regardless of the type of brake you use. ALL brakes pretty much has enough power to generate enough deceleration to send you over the bars regardless if it's calipers, cantilevers, V-brakes or discs. The faster you decelerate, the more force your bike will be pushing backwards and the more "over the bars" force you'll feel.

The only way to fight this is to not brake so hard, and/or to scoot your center-of-gravity backwards and lower. This lowers the roll-over torque given the same amount of deceleration/braking force.

The ultimate limit on deceleration/braking force is front-tyre traction. At some point, even with scooting back and down, you'll have so much roll-over torque that the rear-wheel will be unweighted and you'll fly over. This typically happens well before you overcome the traction limits of the front-tyre (locked and sliding). With sufficient training, it may be possible to lock up the front-tyre and get higher maximum-deceleration/braking force right before it slides, but I don't know of many people with this kind of training.
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