Read Braking Stability, Part I The inability of slipper clutches to control engine braking equally in all gears caused many crashes in the early days of MotoGP. Rider Max Biaggi noted that as soon as the back of the bike lost grip and began to swing from side-to-side during braking, that weave motion could suddenly “diverge”—increase in amplitude without limit—and throw you on the ground. On the other hand, Ben Bostrom’s style was based on braking right to the threshold of weave, his bike loosely oscillating. Fortunately, the necessary technology already existed in Formula 1: the “throttle kicker.” This took the form of a digital stepping-motor, controlling engine idle speed. To better adapt the slipper across all ratios, you just programmed-in enough throttle opening during braking (a different setting for each gear) to cancel or reduce back torque as desired. 
This throttle opening became harder to afford as the fuel allowance was reduced by rule. At a point, Ducati decided to build an “automated Tom Kipp,” a system that would lift the clutch during corner approach, then smoothly re-engage it as power was required to accelerate. When the system proved too difficult to perfect, it was dropped. The idea remains tantalizing. In the present era, braking stability has taken on new meaning with the coming of seamless-shift transmissions. Engineer Ronnie Saner pointed out to me at the last MotoAmerica round that a slightly harsh downshift with the older style of “clunk-shift” transmission can induce a chassis pitch as the completing shift picks up engine rpm. That momentarily compresses the front tire, causing the bike to “nod” as it bounces on its tire flexibilities. This motion doesn’t always show up on suspension travel sensors because much of it takes place in the tires. Yet because it causes footprint pressure and area to vary, it affects tire grip during corner entry; the rider cannot use more grip than is available when footprint is at a minimum. Now that the top teams in MotoGP all have seamless gearboxes, this kind of upset is greatly reduced. A stable bike has more corner entry grip than an oscillating bike. 
Braking stability continues to be an issue, however, because when you intentionally make a chassis softer to increase corner grip, you may at the same time increase its steering-head flexibility. If the steering head flexes, it may create accidental steer inputs—we have seen motorcycles, braked hard, dart slightly from side to side. Even this kind of upset limits corner entry speed, by introducing uncertainty. Marc Marquez, who prefers to brake late and extremely hard, is known to favor a chassis with a stiffer steering-head area than does his teammate Dani Pedrosa. And over the past two years, Yamaha worked hard to improve the braking stability of its bike, which was probably compromised by the chassis softness necessary to stay hooked up in unsmooth corners. Now, so they say, this inequality has been greatly reduced; the Yamaha is now able to combine lateral flexibility with the stiffness to stay on line during harder braking. What will the next layer of complexity be? 
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