running issue

[racefan]

i have an 81 cm400 custom, today i noticed that when i get the rpms up to 5500 or more the bike starts to sputter, bog down but the weird thing is that first and second gear seam to be fine and not do it. if i back off the throttle just a very little bit (around a 1/4 inch)it runs fine and will still pick up speed. would it be something with the fuel system......thanks

[trenttheuncatchable]

Most likely. Add some Seafoam to your gas tank and see if that clears things up.