2000 xr 650 r will very hard to start when cold i have to pull start it some times and when i do get it started i cant touch the throttle or it will stall but if i let it idle it will stall iv tried going through the carb and cleaning it also tryed starting it with half chock full chock and no chock still wont start it has spark and good compresion the engine only ha 50 miles on it but once i get it running and able to move the throttle it runs good and when it warm it starts first kick i live at sea level and the temp is around 50 to 60 degrees