Photo Courtesy of Matt Boyce, WA
We definitely do not recommend transporting your S4 cartop microskiff with it resting directly on the roof of your car, without a roof rack, but since it’s possible, and there may be a case where there is no alternative for doing it, here is a picture that shows how it can be done successfully.
Note that Matt made sure to protect the roof of his car with a thick and wide mattress, and he used three straps to attach his S4 to it.
The big problem is not that uploading, transporting and downloading this 100 lbs microskiff might leave scratches on the car’s paint, but the worst case scenario is that if you don’t attach it well, it might fly away, and hit another vehicle.
Attaching a Wavewalk 700 or S4 to the roof of a car that does not feature a proper roof rack with crossbars is particularly risky in long distance trips, since the boat is exposed to powerful, high speed winds, as well as sudden stops, slowdowns and accelerations that are also characteristic of urban trips.
This is to say that extreme caution is advised, and stopping every now and then to check that the boat still sits well on top of the roof is very much recommended.
Needless to say that in such trips, your motor should be transported inside your car, and never stay attached to the boat.