If you have to remove your carburetor from your CB50J or similar derivative of that machine, it is always a worthwhile precaution renewing the inlet gasket, this will help ensure no unwanted air leaks, with the potential for causing piston or valve damage through a weak mixture. For many of the models listed on the model application list below you can find an online 'parts list' fiche, showing the complete parts availability for your model, why not check it out?