The cross bar apparatus with a u shape or big angle piece to set the frames in would work and use pool noodle things split and around the contact points to keep them from getting damaged.
Real tailgate blankets have straps that goes around the frame so they don't slide side-to-side or bounce around.
Do what all the shuttle companies do. The van I shuttle chuckanut in Bellingham has six position recon in the back hitch, one up 4 position recon in a front hitch, 4 roof mount racks can’t remember the brand. Roof mount is a two person loading job.
Maybe the max weight of the recon would be violated it’s rated for 45 lbs per slot. We’ve only had 4 e-bikes on mine not 6. My ebike is 51 pounds. Super duty one up can handle 4 e-bikes though.
I would box in the front and sides with plywood sheets and then create dividers using either more plywood or pvc piping and wrap the bikes with mover's blankets and put a strap from side to side behind the back wheels to cinch them up against the front divider. Make a second divider from the same materials that goes up against the back tires of the front bikes and repeat the process with another strap against the back tires. You aren't going to get away with zero straps and an open trailer, in my opinion, is going to cause headaches. Blanket wraps are cheap and durable and will prevent rubbing or banging damage. https://www.amazon.com/Simpli-Magic-Padded-Moving-Blankets-Orange/dp/B0BPTH5H7H/ With a completely open trailer, it will be difficult or expensive to secure the front wheels and you'll lose stuff. An enclosed trailer would really be the way to go but it's obviously much more expensive.
Build wheel chocks out of 2x4s and reverse each bike to the next. I assume the wheelbase is small enough to be sideways on the trailer so using 7’ length. chock front and rear. You can lift out the rear and then pull the front over the side of the trailer or us a small ramp to roll i bet you wouldn’t need straps but a quick loop over a handlebar should do
It might be a pain but it is a little easier to load the bikes without the battery installed. I only carry 2 at a time in back of a pickup and Im to lazy to remove the batteries .I can't imagine doing it with 14 bikes. What aventon model did you go with?
Some folks have sent me pictures. I hadn’t looked closely at the RAGBRAI trailer before now. I don’t like the Thule roof style cross-bars for mounting the racks. I personally would get some Airline-style aluminum angled track attached to the trailer floor, and use L-track double lug threaded stud fitting to hold down the 1UP USA roof racks.
I used Kuat Dirtbag fork mounts a lot since they're solid, cheap, and easy to mount anywhere. They require taking the front wheel off though, which I saw you didn't prefer... I'd say a custom wheel chock rack from PVC would work and alternate loading forward and backwards to squeeze them together.
The 1UP USA racks are as good for securing bicycles as the Pit Bull TRS are for securing motorcycles. Use some L-track or E-track to secure them to the trailer, and they can be installed or removed easily. Loading an open trailer is much easier than loading something inside the confines of an enclosed trailer, for sure. It is hard to argue with the weather /element protection and security of an enclosed trailer, however. https://embedsocial.com/admin/media/feed-media/18311/18311147353103898/image_0.webp?v=1692375485
https://huckwagons.com/ But Ebikes are heavy, and may not want that much force on the wheel/fork. 1Up is a "better mousetrap" for bikes, as it is a very easy to use mechanism and only touches the tires. 1Up is the best system for securing bikes, but the number of bikes would make that a very expensive option.
Can you not just do it easily and get a bike race and mount it in your trailer? https://www.uline.com/Product/Detai...NuaNGi75XLYjgD3HNcM7LNWV-Z_pjNBBoC-ioQAvD_BwE secure those in the trailer and just bungee them together? Maybe add some foam to the rails?
@motion, I am considering your discussion of this from the professional aspect. In that you plan to be doing this repeatedly yourself on a regular basis. Or even better yet, have a set up that you can easily train someone else to do for you. It needs to be efficient, quick, and fool-proof. It's also a bonus for your customers to see a well thought out and professional set up. I've been paying attention to how bicycle touring companies set up their trucks and vans for a few years now. Trucks with service boxes and roof-top platform racks are a popular option utilized. Bad enough for your bikes to damage each other, but you can't afford to have one fall off of a trailer in front of another car. 12 fat tire e-bikes are a bit tougher to load and unload than a dozen human-powered bikes, and need to be secured a bit better, with the extra weight. You indeed have a lot of options to choose from. I've been sharing info and links to options I'd consider if I wanted to do this on a daily basis myself. Good luck to you, whatever you decide to do. Please share whatever it is that you decide will work best for you. In case you aren't familiar with this company, they carry lots of great products you might utilize: https://www.uscargocontrol.com/collections/airline-straps-hardware
One way to look at it, I suppose? Labor intensive businesses can be a bit harder to sell I've have found from my personal experience. Folks want to invest their money into a business that is well established, efficient to operate, with growth potential from better marketing, etc, imho. He's selling his dream along with the implementation of a successful business. If it's just a jury-rigged set up, someone will pass on buying his and start their own from scratch. That's what I did almost 30 years ago.
I’d have someone weld up some aluminum with “v” chucks for front that you could lay in the trailer. Roll the bikes into the front chocks then have a piece welded up that you can lay over the rear “saddle area” I’ll call it if the frame and have it bolt to the top rail of the trailer. Roll the bikes in lay the rail over the frames with “v’s” welded to the rail with some rubber over them so they don’t scratch frames. I’d weld some bolts upright to the frame of the trailer and then use a wingnut to secure metal bar to Frame. Drill the bolts and put a safety pin through bolt so wingnuts don’t back out on gravel road. get there unbolt back pull bikes out, etc. Idk - just a thought if you want some easy to use every week.