I have bought a sherco st300 about a month ago. At first it was running okay but the last couple of weeks it is running lean like it's about to run out of fuel.
Have checked the carb, the reeds, the fuel pump and the ventilation of the fuel tank. It all seems to be okay have also changed the spark and cleaned the air filter.
The Jets size are the same as sherco manual refers. I have put the needle on position 1 instead of position 4 as the manual suggests still no major difference. The air screw is at 2 cycles out instead of 0.5. Have also tried the original settings with no results.
The bike runs better when I have the choke on.
Thanks for reading and for any ideas.