Mobility Scooter Carrier

Setting aside the weight distribution, front to back, I assumed nothing based on what you stated in your other build thread. Static loading is one thing. I am sure it will hold up to the 220 pounds of equipment sitting in the parking lot. Dynamic loading is where I think your rear frame support will be stressed and possibly fail on you. Going down the highway at 60 miles an hour, encountering some of the lovely highways I've seen around this country and hit a dip or bump in the road. A gentle bounce in the tow vehicle turns out be the rear end of your PUP augmenting the force and impact of those bumps, creating a strong dynamic loading situation. Think of the PUP's axle as a fulcrum. The further away from that point, the more travel is incurred at the very end. Heaven forbid you have a situation that the road is so rough that the entire trailer bounces and that point moves even further up towards the TV.

I only see one 16 ga. piece of pressed steel serving as the rear frame of your PUP holding your gear on beyond the piece of angle iron closer to the axle. From the pictures and description, you only have two anchor points, with the rear-most one carrying the most significant amount of weight and force. I don't mean to sound harsh but I would not want to be behind this on any given road even if it were only carrying around 60 pounds of water. I hope that I am wrong about this situation and that all is well for you. Regardless, you have to decide for yourself and enjoy the benefits or deal with what happens.

I had a somewhat related situation a couple of years ago with a dual-purpose receiver hitch adapter so that I could add a bike carrier to the receiver and still use it to tow my PUP. Ultimately, after spending time, money and some research that said all was good, I ditched it after hooking it up in the driveway. It did not instill any confidence. I am glad I removed it as it was later found that my tongue weight exceeded the capacity of the adapter when I was actually able to obtain real weight measurements. Care and caution is something we should all exercise even when doing "normal" things much less customizing.

I think that you are all assuming that I am going to haul a 350 lb scooter on this carrier. Not so, the scooter weighs 85 lbs (Including the battery pack)
As I stated in an earlier post. my MAX situation is 228 lbs.
2" Receiver 16 lb, 72 lb carrier, 104 lb generator, 36 lb gas can including 4 gal gas..

Now I normally carry 20 gallon of water in my fresh water tank.
Running it dry equals 160 lbs from BEHIND the Axle.

Moving the microwave and adding my second tank of propane inside the trailer adds to the front (Ball Hitch Load)50-60 lbs?

It's almost a wash at that point, but I'm still going to weigh the tongue loaded and unloaded with the carrier to see what the difference is.

Remember that my receiver has THREE Mounting points. 2 on the frame and 1 on the bumper to carry the load.
I don't claim to be an engineer, but I think that I have it spread out across the frame /bumper combination pretty well.



Frank

You also need to ensure that C-channel bumper can handle the dynamic loading that is going to happen when travelling and going over bumps.

With very little additional weight, a 4" square bumper shown below fell off in traffic.

And the original post here.

Even if you tie into the frame to the point that the rear bumper isn't even required, there's going to be significant force being exerted that could bend the frame and/or bumper and produce a moving projectile sent at drivers behind you when the scooter comes loose.

EDIT: I see now your other thread on the fabrication and construction of the hitch support. I still would be very concerned in following behind that while under load. I would definitely test it on a low-traffic area and then look for any stressed and buckled areas of the frame.

Whenever I've added weight behind my axle, I've been sure to add an appropriate amount of weight to the tongue to balance it. In one instance, I have had instability and sway due to what I would consider a very small amount of weight. Pulling over and moving about 60 pounds inside of the PUP from the rear to the front made it stabilize.

Please prove me wrong but this looks like a recipe for damage.

Looks like I may need to take the cargo carrier off and then weigh the tongue weight with out it on there.
It towed fine that way with my anti sway control in place.
Then I'll put it back on and weigh it again and see what the difference is (if any) My max load is about 173lbs Chair, Carrier and all.
If I put the generator on (and the scooter inside the SUV as before) it will be about 235lbs.

I can redrill and get it about 8" closer but I have to make sure
that I can get to the bed support slots.
I can also move the Microwave from the back to the front.
I like the idea about putting the battery inside. Thanks


Frank Mattox

Check out this video

http://www.youtube.com/watch?v=JT9GkQUpJmM

It was done while towing a trailer with -400 pounds hitch weight, and shows the sway induced by towing so unsafely. Without modifications, your trailer will act the same way, except your car is probably much lighter than a F-350 that will handle the sway without losing control and flipping over.

Fred.

Hi,

I would relocate the spare tire to get the lift as close as possible to the front of the trailer. This will bring the weight forward as much as possible. Right now you are putting about 350 pounds about 4 feet behind the center of the rear axle, and this can transfer more than the total hitch weight to the rear axle, leaving the hitch sticking up in the air (very dangerous).

Without a minimum of about 300 pounds of hitch weight, the trailer will become very unstable while towing. If your hitch weight before installing anything is about 250 pounds you need to keep it around that weight once completed, and make sure that it is not lighter.

Moving the spare tire to the front of the RV will help, but probably not enough to return the RV back to a stable towing trailer.

You might also need to remove the chair batteries, and move then to the front of the trailer, IF the trailer does not have enough hitch weight. I had to do that when I carried a 350 pound 2 passenger scooter with a Jeep Limited. The front axle of the Jeep was getting light when the batteries where in the scooter, so I had to remove the seat, then batteries, then put the seat back before towing it with a large DP.



Good luck!

Fred.

Yours looks very much like the one I got from Harbor Freight.
Simple assembly and. I've had no problem with the carrier.

I'm also considering putting another hole in the tube to get it a little closer to the vehicle. It seems like it sticks out too far.

Thanks for the update.