If you have the same problem that I did fairly recently, I would expect
that it is the actual fuel lines themselves leaking, rather than the
petcock. They have probably cracked and brittled with age. I imagine
that the fuel is leaking slowly but constantly whilst the engine is
running, you only noticed it when you stopped.
I recommend replacing the fuel pipes anyway to be honest, unless you
know for sure they have been done recently.
Martin
03 1200 in Graphite, 39k miles
Bath, England
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