<div id="RTEContent"> Hello Stéphane,<pre>>I was asking myself what parameters in the action >make that the keys return very quickly to their >rest position. I think the most important factor is the rotational moment of inertia of the key stick. This is largely determined by the amount of lead and the position of the lead in the key. For fast return, you want less lead, and the lead should be as close as possible to the fulcrum point (balance pin). In order to achieve that, and still maintain the proper static balance weight, the action needs to have a low ratio geometry. The other factor influencing return speed is the strength of the wippen spring. This adjustment, like all others, is a compromise too. A stiff spring setting will help return the key faster. Vladan </pre></div> <hr size=1>Do you Yahoo!? With a free 1 GB, there's more in store with <a href="http://us.rd.yahoo.com/mail_us/taglines/mailstorage/*http://mail.yahoo.com/">Yahoo! Mail.</a>