if you want any info on JRC carbs , i sell them here in the UK, give me a shout and i will see what i can do to help
... also a pair to my Motoguzzi Monza , all work fine and are simple to set up.
the original carbs were worn out, mainly through lack of use, took the air box out and use a couple of cone air filters, works a treat , there is a cable conversion for the fuel enrichment which is not needed on the v50, but is on the v65.