Guys, I have a 02 WR426 with totally stock jetting. It has all the typical mods: gray wire, airbox lid removed and throttle stop trimmed. In the SoCal desert at Ocotillo Wells occasionally I get some popping when I close the throttle abruptly but I've been told by numerous people not to worry about it. This past weekend I was in Baja -Tecate, Mexico at about 4000' and was frequently getting some LOUD popping-backfiring when I closed the throttle abruptly. What should I adjust on the carb to compensate for this. Is it safe to assume at the higher altitude the jetting was too rich?? Any advice would be greatly appreciated. Thanks.