I don't have this problem, but it also sounds like you need to synchronize the carburetors and open up your pms some. Out of synch carbs and a lean condition can cause a sticky ideal. Take a look at your plugs, that will tell you if you have a lean condition. The plugs need to be a tan/gray color.
This link will help you read your plugs.
http://www.ngksparkplugs.com/tech_support/spark_plugs/faqs/faqread.asp
Here is a picture of the synchronizer screw (the one on the left, black knob is for the ideal). Use a 7mm wrench to turn it and use a manometer hooked up to both carburetors to synchronize both carburetors.
