I just built this custom old skool bobber bike. Built from scratch by me. I have a 66cc SD Stinger on it. The whole float assembly in the carb took a dump, so I put my old carb from a 49cc engine on. I switched the jets and put it all back together. Then I fired it up and NOW IT HAS A VIBRATION PROBLEM? You can feel it up and down the whole bike when you ride it. Any ideas what's wrong, or what I could do to reduce the vibrations?