trailer wieght for an ultra light build

[MidTNJasonF]

if you want light weight, go with a foamie, till you get the bike(s) on the trailer and the bare weight of the trailer frame you've got a lot of weight to stop and go with on a small car.
I tow my TD with my 4 cyl Focus, I figure I'm around 1200 lbs with all my gear, towing at the 2000 lb limit for the focus in the rest of the world would not make for an easy drive and be very hard on the car.

As I stated in my first post this will be a bare bones foam build. I am just trying to work out a way to get the base trailer as light as possible as well. There will be no plumbing and minimal 12v electric for a few LED lights. The only wood structure will be around the window, side door, and the rear door. I need some structure around the rear ramp door to support it since it needs to be strong enough to handle the weight of the bikes.

sorry missed that somehow...
would a single plank type ramp be lighter than the whole door being reinforced? then the door could hinge up to make an awning, made of foam it would be super lightweight. the plank could store under the trailer floor.

Yes I am on the fence about that. I certainly could go with a simple stow-able ramp and save some weight on the door. It would eliminate some of the complexity of a strong enough hinge to support my weight and the weight of a bike as I am loading or unloading.

If I go with a single side hinge or a double side hinge door setup on the rear I could use that as my main access door as well and save the weight of a side door. If I do go with only a rear door I would then need only a window for each side and a roof mounted fan vent. With a ramp rear door or even a lift up rear door to make a canopy I would need a side door and that would be added weight for hinges, frames, and latches.

The only reason I would not be keen on a hinge up door is my total height will be just a bit over 5 or so feet. I am 6' 3" and would have to duck under it. I will probably just tote a 10x10 pop up canopy to setup over the back of the trailer.

[MidTNJasonF]

Ok, Last round of planning before the build (and revisions to the plans) begins.
I looked at the ready built trailer I found on Craigslist and it was a Harbor Freight folding 4’X8’ in really good shape but it was apparently an older model that came with the 8” wheels.

I passed on it since:

A) I would have to spend $50~$75 per wheel to upgrade to 12” or better wheels.
B) I would have to modify it anyway with added strength in a couple areas and to fix the hinge point solid.
C) He would not budge off his price of $200. A new one can be purchased for about $270 out the door with the 12” wheels.
D) I would have to modify it further to cantilever out my deck 6” per side to get my desired 5’ width.
E) I would have had to make additional cuts/joints to incorporate the wheel arches into my body.

So I am back to building my own but I am going to pick up a tilt trailer subframe that is ready to build a deck on it. It already has nice aluminum 13” wheels and radial tires, axle, springs, coupler, and lights attached so I can save some money by buying someone’s unfinished project.

I am going to remove the hinged straight tongue and just add a welded A frame. I do not have my sketchup tool here at work so I am trying to dig up my high school math skills and lay it out on paper.

I want the A frame to extend back under the deck fairly far to for support. I would prefer to use a standard 2” A frame coupler that is 50º included angle.

How long of a tongue length (forward of the front cross member) should I target on an 8’X5’ 1100 lb trailer?

Using the trailer balance calculator previously linked in this thread if I plug in the weight of my motorcycle fairly far forward, an extra 150lbs near the rear of the trailer for additional gear and the door frame, and a total length of 132” (may change) it looks like an axle placement of 48” (dead center of the body) will give me just at 100lbs of tongue weight which will be just shy of 9% of the trailer weight.

Does that sound right to everyone?

My wheel chock will be installed in such a way that I can move it forward or aft in 6” increments for a total of about 1 1/2’. This along with the ability to place the weight of my other gear anywhere along the length of the trailer should allow me to get a nice balance on the trailer for towing.

[MidTNJasonF]

Oh and I am ditching the Aluminum frame idea for now. I decided against if for both budget and time reasons. I can weld the steel at home while I would have to pay a friend with a TIG welder and a fab shop for his time to weld the aluminum. I would also be at his mercy for scheduling as he would try to do it off hours.

I can also pick up the steel locally any day of the week while I would have to order the aluminum and wait for it to come in.

I might try to do a second build or rebuild on an aluminum frame at a later date if I find a deal on something down the road.

[MidTNJasonF]

Got the trailer home. It sure seems bigger than I had imagined.

It is also slightly bigger than I thought physically. The side rails are 3" X 2" 14ga (0.083) rectangular tube. The tongue is 3" X 3" with a heavier wall. It is what was left of a cut up boat trailer.
I have 64" outside rail to outside rail so that is actually good. With 2" walls that will give me a real 5' interior width.

It is currently just a perimeter frame with a front and rear cross member. I will need two additional cross members I think ad I will be removing the tongue and replacing it with an A frame of 2" X 2" 0.120 wall.

I am hoping to get some weights on the axle and components before I start welding this weekend.