first mistake..taking it to a so-called none honda mechanic..lol..as for the elavation issue..i never pay any attention to this..as most atv's will run no matter what..and yes..your correct on a sticky float..this is what is sounds like to me..your not getting enough gas into your carb..my advice..remove the carb..remove any o-rings..buy some carb spray cleaner ( gum out works best for me )..remove all your jets..if you remove the air/fuel mixture screw needle from the front bottom of the carb..by all means..DO NOT LOOSE THE TINY WASHER !..also..thier is a very tiny o-ring down inside that hole..if you use a air compresser to blow your carb out after you give it a good spraying of the carb cleaner..make sure to dig this tiny o-ring out of the air/fuel mixter hole..or the carb cleaner will destroy it !..if i were you..i would inspect your jets..see if they are bright and shinny ?..if they are not..then this so called no-honda mechanic never over hauled your carb with new jets. before you put everything back together..check for fuel flow to your carb...make sure your getting a good flow to it..it never hurts to install a in-line fuel filter ( you can get one from any wal-mart in the lawn mower section )..these can save you alot of trouble down the road. keep us posted on how it does.