Are you referring to the forthcoming engineering tomb or the weight of Tony's tongue lashing?

Jarrod - as far as I am aware, the tongue weight is the downward force exerted at the tow ball coupling of the trailer. This is predominantly determined by how well the boat (and outboard) is balanced on the trailer (although, yes, extreme forward or aft loading of a boat will affect this to some extent) I read somewhere that there is an ideal weight - a lot of figures determined by the boat, trailer, position, length of boat and trailer etc etc.

When I refer to balance - I mean front to back, not side to side (though that too is important).

Some home made, poorly made, or poorly matched trailers can result in too much forward (boat) mass causing excessive downward weight at the tow ball coupling and also severely impede good (and safe) towing. Of course that is also true if there is noo much weight displacement towards the rear of your trailer.

Sorry everyone for dragging up the thread but i finally did end up getting a boat, a 4.7m mustang half cab with a 70hp 2 stroke johnson on the back... i know perhaps not the biggest boat around but its not to bad for me as i can put it in on my own and there's a bit of room to sleep in if i do a overnighter... now to wait til summer to get it out