I don't have to log in every time I post when I go to Mikes then again I never did the sign up thing on his page I just post, you might ask Mike there might be a setting to auto log you on each time, I would not quit using his board because of a minor annoyance thing I would figure it out... it is probably just a setting thing you over looked?
My reply on Mikes page was
" Hmmm see you could be causing or creating your own your own problems with the home made air filter setup, the stock intake boot as with all ATV's and
motor ((
Internal Combustion Engine ? )) cycles is tapered from the air box to the carb they taper it down to speed up the air as it enters the carb so it will properly pull the fuel from the carb gets, you need this convergence to make it work properly I would search out ebay for a stock air cleaner parts, if it is a modified machine running your setup can be ok because modified machines require more air but your whole carb calibration will probably need changed to work with your system, on my 250 when I went to a bigger carb I used the intake tube from a FL350 so it would fit the bigger inlet bell on the bigger carb but it still has the convergence needed to maintain the carb signal, modified intakes can have their advantages but they can also create a bunch of problems."
Again I said "could be" it is hard to diagnose things like this over the internet I do know that manufactures go to great lengths and expense to develop the tapered intake boots and air boxes the carb relies on a pressure differential to work eliminating the taper boot allows more air flow but with less velocity, less velocity = less ability to pull fuel form the carb, less performance.
You need to check the jetting on your Engine to see if you have a jetting problem, if the jetting is ok you need to check the inside of the Engine to see if the top of the piston and head has a layer of carbon that is causing your problems.