Fuel Mixture Screw - XS650 - 1978-1979

Fuel Idle Mixture Screw with O-Ring Fits: XS650E/SE/F/SF/2F(1978-79) Stock Mikuni BS38 CV Carbs. Beware!Carb idle mixture screw O-Rings included may or may not fit correctly in your Mikuni BS38 CV stock carburetor. The O-Ring in the carb as originally supplied by Mikuni/Yamaha varies in fit and size and we have found it impossible to match or guarantee a proper fit. No alternatives can or will be supplied. The mixture screw and matching O-ring was never sold or supplied by Yamaha or Mikuni.