Couple of things, first they say that as the lifting points are not rated to carry much weight above what the dinghy weighs, however it’s not the bow that you should worry about, it’s the stern, the bow will weigh less when the motor
is on, because the lifting point in the stern are ahead of the motor and the motor will act like a fat kid on a see saw, lightning
the weight on the bow.
My advice is to get an outboard
mount on the rails and always take the Motor off of the dinghy whenever you are going to do any kind of crossing and only leave it on when your going a short distance in protected waters.
Also your going to find that even if you find a way to support it so that everything is good, the excess weight is going to cause the dinghy to swing back and forth more aggressively and your going to have to really lash it down good to hold it tight. The extra work
in lashing off down pretty much equals the work
to remove the motor, so just remove the motor.
Those handles are soft and flexible and you can’t use them for support for that reason, and they could rip a hole in the tube. If your bound and determined have someone weld strong lifting shackles to the hull
, onto large support plates to distribute the load, say 6” square 1/8” plates.
But I suspect your much better off removing the motor, your davits can hold it, but over time things fatigue, maybe the railing the davits are connected to.
On edit I see it’s not a RIB
, just take the motor off.