Hi! Anyone knows what are the oem specs on carb needle (letters and number) for a 1986 atc 250r? I have NR146 but i believe its not oem keihin. Having midrange issues and thinking to put oem carb parts on my stock engine. I only have reeds, kn filter and rear muffler. My main jet is keihin #145, pilot #42. Any info or advice is greatly appretiate it!