[QUOTE=cczjordan;14479233]My btta engine has a problem with low end, previously it run good but suddenly it dont have low end power n will surge. Some guruS told me the main bearing is tossed. Any idea?[/QUOTE

To check to see if main bearing is toast, run the engine on the starter box. If you hear a ringing noise, like metal on metal contact that goes away when you place your hand on top on the cooling head, then the main bearing will need replacement.

Also, check to see if all your fuel lines and fuel clunk are good and clear, check and replace gaskets and springs, then retune and see if problem persists