Bike Rack Questions-- Again

we took an idea from a camping friend. we have a bike rack for 4 bikes that goes into a hitch. we had a sheet metal shop make a custom plate with a receiver hitch mounted on it, the plate is then attached to the fifth wheel hitch on the trailer. the bikes ride in front of the trailer. a family that we camp with has 4 kids. they have 4 bikes on the 5er hitch rack and 2 bikes on a roof rack on the truck, along with 2 kayaks, and the rest of the kayaks inside the trailer. I don't have a close-up picture of the bracket that is on the truck. bikes will go on this coming weekend, if you are interested I can take pictures and post them in a week.

Rear mounted bike racks can be done however they are problematic due to the excess bouncing that occurs (school bus effect)and the simple fact you can't see the bikes while traveling.
For those reasons I prefer an Arvika pin box bike rack. There is no bounce at the front end of the RV and bikes are always in view.
Arvika racks are made for 5'er and TT's.
I have been using an Arvika rack for about 7 years. I used the rack on my TT for a few years and the adapted it to my 5'er.
Arvika bike rack images

We have a small TT, and when we bought it, the dealer advised against any bike rack in the back of the trailer, for just that reason! We tried roof top racks, didn't work, and settled on a front receiver hitch for the SUV. Bick rack fits on perfectly and they don't bounce around quite so much. The receiver was from Curt, cost right about $200 and took less than an hour to install myself.

Have you ever road in the back seat of a large school bus?

That back seat tends to get a lot of "air" when going over bumps in the road.

The exact same thing happens with bike racks hung on the back of any trailer.

Basically there is no real safe bike rack when it is hung on the rear of a trailer.

Some folks have even resorted to DRILLING HOLES from the outside THROUGH to the inside and running a bolt all the way through. Then using that bolt as a means to MOUNT the top of the bike rack to the trailer.

The idea is to stabilize and reduce the swing forces on the rack.

Personally after almost losing a bike rack along with two bikes I abandoned the idea of hauling bikes on the back of a trailer. Just to dangerous (not just for the bike but other drivers).

In my case I bumper pull so I make a rack that sits over top of my truck bed.

In your case I think there may be a bike rack mount you could get which uses the 5th wheel mount on the trailer to attach a bike rack. If not the case perhaps consider a front mount on your truck. Or as others do, put the bikes INSIDE the trailer, lots of creative ways which are safer...

We use a "hitch hauler" with the bike adapter. it works well for us. They're about $50 & $30 for the adapter.