This webpage will be your best friend
http://www.650ccnd.com/ht.htm
sounds like the low speed jets has some dirt in it clean the carb
Bad fuel mixture, jets, carb adjustment. try to keep engine reved high
buy a jet kit and take the bowl off your carb and and put your jets in
I just rebuilt my Edelbrock 1405 Preformer carb. During the rebuild once I had the carb almost completely dissassembled I removed all four jets and replaced them with new ones from the kit.
There could possibly be somthing stuck in your carb on one side or the plug on that side could be mis fireing or your jets could be off on that side
on a computer controlled vehicle you have to reprogram the computer and on an older vehicle with a carburetor you have to change the jets in the carb.
bore the cyl then drill the jets in the carb and then change the sprockets that should give u a lot more power
Only adjustment on it is the fuel mixture screw (on the bottom of carb) all the other jets are fixed, and the only way to modify is to buy new jets and install them.
fIRST CHECK THE JETS IN YOUR CARB, THEY HAD A BATCH COME IN WITH THE WRONG JETS INSTALLED.
250
I am pretty sure its 300 Stock main jets in a Banshee are 200 not 300
42 pilot 150 main for stock Keihin butterfly carb.