Recently finished up a project YZ490 conversion on a Yamaha blaster frame and I’m having a very peculiar issue. Thing does NOT like to start, I’m talking if it’s cold you have to pop stsrt it for the better half of 20 minutes. Issue being that the carb is dumping fuel into manifold whenever I shut the thing off. Once it’s running, it runs like crazy. Once it’s hot, if you keep it wide open it normally starts on the second kick, If you don’t let it sit for more than a minute. I have tried two different carbs entirely and all sorts of jets, needle positions, float height, etc... cannot figure out what’s going on. Thinking the only common thing between the two carbs is the angle of the carb, it sits slightly titled back (toward the motor) but I’m grasping at straws.. any ideas??