if the filter is clean then adjust the "H" setting on the carb - the top casing of your saw will have three small holes in it marked "H, L and blank". The H setting is high speed running. turn the setting in and out whilst revving the saw - I would guess your saw is running rich and will need this setting screwed in a half turn - make sure the filter is clean and thesaw is warm before you do this.
Steve
March 2009
check the air filter under the handle cover it might be plugged up and starving it for air
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