Looks like Yamaha list the "L" the same as the "K" .
Pilot jet = 60
Main jet = 290
An old magazine tells me the Yanks liked to run a 280 main with holes cut in the airbox.
Stock standard they reckon the 250K lacked a little bottom end power, and the 250L had to much.
My first 250 was an L, and it would pull like a 500 from idle, then fall in a hole at the top end.
Good luck with the jetting.
