Leaking Carbs

[sprint]

Thanks for the replies and advice.

Manual tap not a vacuum one and currently the carbs are in the vice being fed from an auxiliary fuel supply.

However, tank was cleaned when I got the bike in Jan and tap is leak free, fuel in tank not leaking through tap.

As indicated, all jets, valves etc have been ultrasonically cleaned and bowls have no dirt.

Guess I will have to put the carbs back on and see how it goes as I still have rough running and black sooty plugs on No's 2 and 3 to sort out.

Have fitted new points and condensers, old points were pitted, so hoping that will have solved that problem?

[Bonneville]

You probably know this but worth mentioning. You said you are feeding the carbs off on the bench with an auxiliary tank? Make sure the tank is no higher than the bike tank would be as fuel pressure increases as you raise the tank.
I used to hang mine off the garage ceiling then wondered why all my carbs overflowed...