UPDATE 10/29/2018:

I purchased a James Baroud Grand Raid XXL and it WILL NOT sit flush on the crossbars of the prinsu rack. The side rails of the rack is actually about 1/4" - 1/2" taller than the crossbars.. and being the James Baroud Grand Raid the footprint of the rooftop tent is wider than the rack itself..

What do I have to do to secure my RTT down to the Prinsu Rack.. Anyone help?

https://imgur.com/a/Bh8jbXc
I did a temporary fix and put it down on some wood slats... Anyone out there have a Prinsu rack and could explain how and what they did to get center support for their rooftop tent?

I just went through this with my JB Explorer Evo.

I just ordered additional rails, mounted the rails directly to the tent with a small homemade spacer sitting between the rail and the tent (using a thin strip aluminum from lowes, cut into 4 equal sizes drilling holes for each bolt to slide through).

I then trimmed the excess bolt thread from the mounting hardware so it didn't contact my roof (it would have with my supplied hardware), and then mounted it that way. I worry about flex if it's mounted too high off the rack, which is why I went the way I did.

I also built a ramp out of 2 2x8x12s and 1 2x8x10 so I could lift it on and off the roof with just myself or maybe 1 extra set of hands.

Why are you needing spacers? I didn’t install any spacers.

I am curious how you did the mounting system..I am going through same trouble with my tent and would love to see what you did for putting the tent on top of the roof rack..

I'll see if I can get a photo of the tent tonight and upload it. It's currently not on the truck, but you should be able to see the rails "permanently" attached to the tent bottom.

All I do is remove the rail side bolts and lift the tent off the truck. It's honestly not mounted any different to the prinsu rails than what you would do to with the stock crossbars.

Its due to the poor quality of the rack, not sitting level. I needed the spacer to sit between the rail and the tent due to how the tent rests on the side rails preventing the rails from lining up with the mounting slots... was millimeters off, but enough I had to fabricate a few washers to drop the rail lower.

It was such a huge pain in the @$$, I almost ordered a frontrunner rack as I was trying to get the tent mounted.

I was asking more about the process of you getting the tent on top of the truck by yourself

Your tent doesn’t have rails on the bottom that the mount to the crossbars of the rack? How does it attach? I had plenty of issues with my Prinsu but mounting an iKamper Skycamp to it was not one of them.

AAAh. I basically just built a wooden ramp for it to slide up. It's wide enough that my crossbars fit inside of it, and I just push until it's on top. It definitely helps with one extra though.

It does, but my prinsu rack side rails are far from flush with the crossbars. When I mount the crossbars to the mounting rails of the tent, and tighten, It does not reach the side rail mounting holes for the crossbar to be threaded through. Its why I had to add an aluminium space on top of the crossbars, between the bar and the tent so that the bar would drop down enough to make up for the less than flush side rails and rack.

Basically, my "Flat rack" is anything but. Instead of being ______ front to back and side to side, it's concave like a bowl, so nothing sits perfectly flat. It has nothing to do with how I mounted the front feet either. That portion of the rack sits the flattest. The portion between the two stock rail mounting locations is terribly out of line. I had to use 6 or 7 washers just to get it as straight as I did.
I wish I had gone with a Frontrunner (Or SSO) like I originally intended, but I was swayed by the price point and the fact that everyone on here loved theirs. I'll never buy another CBI product after this, and I'll warn others from here on out with my experience.

Interesting.. if ever you get around to taking photos/videos of the setup, I would love to see it. I am trying to do something similar but have gone off on crazy tangents which make them fail.

It's going to be a few months before I can snap an in-use photo, but here are some videos I used as inspiration:

Link to thread and video



The principle is the same for each, but I feel my way is safer and more stable than the first gentleman. The second guy was just ingenious.

Edit:

I used these at the end of my ramps. I mount the metal ends on my rack with rags underneath so they don't scratch my rack, then I use a ratchet strap to my sliders secure the ramps while I'm loading. It places a load on the ramps so they don't move about while I'm wrestling with the tent.

To do all this I bought two 2x8x12 and one 2x8x10. I cut up the 2x8x10 into equal lengths and screwed the pieces into the two 2x8x12's to form one solid ramp.

Looks kinda like this, but with the cut 2x8's running perpendicular to the 12fters, mounted underneath, so I have a smooth sliding surface for the tent and a solid ramp. It's heavy, but I don't worry about sliding or bowing.

I get it now. I misunderstood what you were trying to say. I was a picturing a totally flat underside of the tent and that the top edge of the side rails sitting a hair higher than the top of the crossbars was the problem.

Ok I'm on the fence I'm about to go pick up a iKamper RTT and need some input.. How does it mount to the Prinsu? I need to be prepared to mount it up top when I go get it. Do I need the half inch spacers or 1.5" spacers.

Anyone?

I just set it down on the rack. The Prinsu rack is a piece of shit but the iKamper Skycamp sat on it just fine.

Did you sit the iKamper directly on top of the rack? Isn't the iKamper sitting on the side rails only since the footprint of the iKamper is wider than the rack?? So no center support?

I actually went with a James Baroud Grand Raid XXL and I'm clueless as to what I have to do to fix this issue.

https://imgur.com/a/Bh8jbXc