Over the past year, many MotoGP riders and watchers have noted how smooth Jorge Lorenzo rides, and that it is one key to his success in 2012. There is no question you have to be smooth to ride a 260-horsepower MotoGP bike, but the same can be said of any motorcycle.
Being smooth encompasses many aspects of riding: Your movement from side to side in transitions, throttle control, applying the brakes, steering inputs and gear shifts are just a few examples. One area that people often struggle with is the initial application of throttle when exiting a corner – smoothly making the transition from off-throttle to on-throttle. I have seen room for improvement with many riders I have worked with, from first-time track-day riders to expert-level racers, and it is something I constantly worked on myself over the years.
Why must the initial throttle opening be so smooth? When the motorcycle is in mid-corner, 100 percent of the tires’ traction is going toward cornering forces; none is available for acceleration. To accelerate, you must reduce the cornering forces (by lifting the bike up from maximum lean) to free up some traction. If you are abrupt on the throttle and the bike accelerates suddenly when you are still at maximum lean, the tires cannot handle the combined forces and the chance of a crash increases; you must lift the bike up a significant amount even before you can apply the throttle. On the other hand, if you are able to smoothly open the throttle just a fraction, you can begin accelerating when the bike is more leaned over – and earlier in the corner.
For inexperienced riders, a lot of the abruptness in throttle control is a physical matter – they are simply gripping the handlebars too tightly to have the necessary finesse on the throttle. This is one reason why it’s important to hold onto the motorcycle with your lower body and support your upper body with your torso, leaving your arms free to better work the controls.
Riders with more experience sometimes get overanxious in the corner, and apply too much throttle at once – thinking it is the way to get as much acceleration out of the turn as possible. I see the results quite often in data taken in long, sweeping turns: The rider opens the throttle too abruptly for the lean angle used in mid-turn. The tires can’t handle the combined acceleration and cornering forces, the motorcycle begins to run wide, and the rider must close the throttle. With speed reduced, the motorcycle comes back to the correct line; the mistake has been corrected, but then the rider opens the throttle even more aggressively to make up for lost time, and the cycle repeats. The rider ends up opening and closing the throttle multiple times in the corner and feeling as if he is at the edge of traction, and yet other riders are pulling away from him.
Data for very experienced riders shows a very smooth throttle opening, and in any given turn the throttle is opened only once, and then held open from there – no multiple transitions from off to on and back again. Many top riders work tirelessly on that initial throttle response and that includes working on the setup of the motorcycle to make engine response as smooth as possible. Eccentric throttle tubes can help, as they open the butterflies less for a given rotation of the throttle tube at small openings (and make up the difference at large throttle openings). Fuel and ignition settings at small throttle openings can also be altered to change response.
There are many other aspects to riding smoothly but the initial throttle opening is one of the most important, and one that many riders could benefit from addressing.