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Posted

Hi I have a 2005 yamaha 400 big bear. When I run it without the breather cover on it runs good. This is without the air filter. As soon as I put the lid on and snap it down tight I have no middle or high rpm. Any ideas. I've checked the pipes from the air breather and all are clear. No animals nesting in them.

Posted

The behavior you're describing sounds like the jetting is rich. When you cleaned the carb, did you use any hard objects to clean out passages?

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Posted

Shifter shaft was broken so it sat for awhile. So with it sitting so long I figured I would clean the carb when I received the new shifter shaft and installed it. I noticed the intake rubber manifold is hard now with some tiny cracks. I'm guessing it's starting to get old.

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