If you're talking about the stock item fitted to 02 bikes not sure "work perfectly" is entirely accurate, Guy. Always feels a little soft & fragile to me. First time I removed tank, thought I'd turned it right off, but thread had snagged part-way (maybe a bit off grit) & when pulled pipe it flooded the shed w fuel, couldn't get the b****** pipe back on, petrol pouring everywhere.
I've never been able to get mine to shut off completely & it'll always dribble a little fuel when I take tank off.
Maybe I just got a bad one ?
KB
Maybe I should have said work well if you add a bit of lube now and then- the manual tap on Helen's V11 Sport did seize open when I did not lube it for years, and had to unseize it in the vice. Still prefer them to the horrible electric petcocks which are very fragile, and have changed the electric petcocks on my other Guzzis to the old style.