I have a YT 125 and the thing starts really good about half the time and then it just wont start. when i come down to the shop the next day it will start right up. it isnt flooded becuase every time i drain the bowl becuase it isnt starting there is the perfect amount of fuel in there to start it.

 

Does it only crank fine when it's cold and always hard to crank when hot?

Or does the engine temp matter?

Two things come to mind.........a bad coil.......or a choke circuit problem

 

thanks