Hi,

The adjustment of the cam allows a little more fuel delivery and earlier, I'm not sure you really win 500 but rather 200 rpm max. There are several important things, on the seal of the cam there is a reference (0), you must remember that location (this is the original one) by turning the cam you arrez varying fuel supply at the beginning acceleration, then you can tighten the nut notched five clicks (to start) always remember to remember what you change so you can return to the original if you wish. During this operation does not touch the accelerator pedal. If you adjust the screw notched excessively, you will have a big black smoke when you will speed, finesse and not having the big smoke (thick smoke means excessive adjustment).

best regards
Petit caillou.