I have a 600 twin 2002,gets decent gas mileage and runs great,but smokes like a chimney at idle and *leaves oil on belly pan.I run it at altitudes between 500-2500 feet.I would like to clean *up the jetting a tad.

If you look on your throttle cable you will see the oil adjustment (its hidden under a rubber boot) and change it.
You really shouldn't be able to set so low as to burn your motor up just adjust slowly and this should clear up your problem. * http://www.snowmobileworld-s2.com/forums/iB_html/non-cgi/emoticons/devil.gif