Ok I have an 87 trail boss 250. Was running fine then started bogging down real bad through mid throttle and smoking real bad like it was out of fuel [it’s still oil injected]. Would idle fine and wide open throttle was fine only had a problem in mid throttle. Cleaned carb filter plug no change. Sprayed everything down with brake clean looking for an intake leak and found that the base gasket under the jug was sucking air. Sprayed it and it died instantly every time. Tore it down and replaced the gasket. Can spray it down now and it just purrs. Runs a lot better. But still acts a little sluggish in mid throttle. Any ideas?????? Fouled plug maybe??
