Weight limit on wall mounted bike rack

The bike rack on my 2004 Nuevo is mounted on the back wall as is common.
The rack is rated at 60 Kg max.
Does anybody know what the max weight that the wall will take ?
I want to carry two electric bikes at around 20 Kg each.

https://www.autosleeper-ownersforum.com/t32615-bike-carriers-for-electric-bikes?highlight=Bike+rack

Carrying ebikes on a Fiamma or other rear mounted bike rack has been discussed a few times. The above link might be helpful.

As you will see opinion is divided whether the wall mounted rack is suitable or whether it would be safer to use a tow ball mounted rack. For ourselves we carried one ebike and one regular bike on a wall mounted rack, but when we bought the 2nd ebike we used the tow bar mounted variety. Apart from the weight on the back of the van, there is also the issue of lifting these heavy bikes onto the rack.

Two e bikes on our Fiamma Pro C carrier each weighing 20kg minus batteries of course. So 40kg plus weight of carrier at 7kg leaves at least 13kg under the maximum. Plenty of spare for stress from any road bounce. 

I queried this with AS tech support and they confirmed that the Fiamma rack (if installed properly) is rated at the full 60Kg when on the back wall of a Nuevo (04).