If you did breakin and tuning without the filter then I'm sure your needles are too rich, since there's going to be more air flow without the filter. And when you refer to the "foam filter," are you talking about a foam pre-filter, or have you been running with no filter at all? If the later is the case then slap that thing on, ziptie it and fiddle with the thing as long as it takes to figure out the carb settings to get it running. Otherwise you're running a very great risk with an engine that's not exactly cheap... if you haven't already shortened your piston/sleeve life.