And what's this mysterious lever?
Following text is just the Italian text put in Google translate.
"Looking through the box, to the most careful observers did not escape a particular characteristic of all Honda. It is a small lever under the left handlebar, in the same position where it was fixed the rear brake lever to the handlebar, such as that used by Doohan. The lever of the mystery is shown in the photo on the left. Its function is different, however, and try to solve the mystery was Valentino Rossi. "I do not think that would serve to restrain, the Honda riders use the classic pedal" has guaranteed the Doctor.
Then he assumed his function: "I think that it serves to put the transmission in neutral, even if it's just my guess." The seamless exchange has the advantage of canceling the transit time between one gear and the other, always ensuring traction during changed. In practice, and greatly simplifying its operation, it is as if the change had always two gear, being able to switch between them in a very quick time. In a traditional motorcycle exchange the idler is placed between the first and the second, but this would cancel all the advantages of the seamless transition between the two gears.
"In order not to lose them - continues Valentino - the crazy has been moved below the first, but this could be a problem when you scale the brakes. There is a risk that put the crowds. Then, they could have stuck his engagement with the foot pedal. "The explanation for Rossi nell'inedito role of technician is flawless. I wonder if Honda will confirm the theory."
Origin:
http://www.gpone.com/en/2013082511237/Rossi-svela-i-misteri-della-Honda.html#ixzz2d1ociPkp