The issue with adding a hydraulic bike lift when previously discussed was that the ones available cantilever off the engine cradle or the existing hitch. The standard hitch has a 1000 pound tongue rating and 10,000 pound towing limit. You are unlikely to exceed the towing weight limit, but it is probable the 1000 pound tongue weight limit will be greatly exceeded because instead of being 6" or so from the rear bumper, the CG of the bike and lift is probably going to be much further out giving substantial leverage. Hanging a heavy bike and its lift depending on total added weight and distance from the rear bumper is likley to be far in excess of what the rear structure was designed to handle.

There are some coaches that show evidence that at one time the weight limits on the rear tongue have been exceeded. The rear cap on the coach typically has stress cracks at the attach points and horizontally across the rear of the cap.

Peter has fashioned a carrier for his Smart car, but his design transfers the loads in such a way that he puts the vertical loads in an area capable of handling those loads and it is likely most of the loads on the engine cradle are horizontal.