Engine boggs down

My 87 kz305 LTD boggs down at low r's, when I get going it's o.k. when I shift, boggs down again. Any info?

Here is your other thread on the same topic... www.kzrider.com/kunena/2-engine/610918-boggs-down

And you never answered the question posed therein: is the bike stock or modified and what maintenance have you done?

Is the complete stock airbox installed w good air filter? Is the airbox cap properly installed & good fitting? On some 440 models, the airbox cap can be installed wrong, leading to a vacuum leak & poor running >> the 87 305 airbox cap fits kind of similar to the 440 Ltd.


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