hi,found some o rings worn out, & quite a bit of corrosion/dirt. just could not get the zx to run very well after electric choke switched off. so bought & fitted a replacement carb to the zx today. from a north east uk breakers yard. came from a daelim 50. seems to work fine.but is fitted with a 75 main jet, while the zx carb has a 80 as standard. any problems with leaving 75 jet in ? otherwise i will change it.. regards, steve.