about to undertake conversion of a set i scored off a monster 600 (02) needles and jets are similar size i`ve read and monster manifolds were included good so far also will get 600s air box hope it fits under tank .will use a carb cleaner spray for good measure .my question is about the wiring connection on side of carb, whats it for , do i need to attach it into the wiring system .i read ( i think it was that poobar chap ) their suggested method for conversion to mikuni`s found it very informative 750 paso 1989 750 monster 1999 suzuki gsxf 750 1999 norton dominator 1956

A picture would help, but my best guess is its a Throttle position sensor.

It's carb heat, to prevent icing.

I'm not aware of any electrical connection to the Mikunis. They don't have a TPS and the carb heater is from the oil line that attaches to the float bowls as an option.

Some Ducati Mikunis came with engine-oil carb heat (girlfriend's 900SS FE) and some came with electrical heating elements under the throttle plate (mine).

And you will need carb heat when it's 40F and foggy or rainy. I once rode 30 miles on the interstate with the throttle stuck open from carb icing, feathering the brakes to control speed. Lost my nerve after a while, hit kill switch and pulled onto shoulder. A minute of non-operation melts the ice.

That was with the Weber. Mikunis do the same until you switch the heat on.