sick bike!

[ELubejko@webtv.net]

My bike has not been running to well lately. It runs great except between 4500 and 5500 RPMs. In this area, the bike starts to spit and sputter. Kind of like it is starting to run out of gas. I tried running the bike with the gas cap open and this did not help. I thought it might be a venting problem, but I guess not. I did clean the carb and this only fixed the problem for about a week. Does anybody have an idea what this problem could be? Ed Lubejko COS