Ruggedized moto hauler with a RTT option

I've been considering a trailer to haul my motorcycles that I could camp from. Doesn't need to haul multiple bikes and it must fit in one side of a 2 car garage along with 2 motos and an e-bike. The other side of the garage is spoken for.

That eliminated a 5' wide trailer since I would be upgrading the wheels to something larger. I looked at all the big box utility trailers and most weren't built to the strength I'd prefer. Time to do it myself.

My goal is no flex and minimal if any rattling when it's done. Pretty simple design, 4x8' tube frame with medium height sides, removable upper structure that holds a RTT and allows a motorcycle to be hauled. 3500# axle, 15" 215/70 15 wheels.

Bought a couple essential tools for this project. HF prota band with a stand, gret tool that's gotten allot of use so far.





And I picked up a tiny 220V stick welder for the structural welds, I have access to a 110V mig
for the rest of the welds.



Some planning and a trip to the metal store and I was ready to begin.


I went with .180 2x2 for the outer frame, .120 for the cross members. This trailer won't be very loaded nor used on difficult 4x4 trials so it's weight isn't as much of a concern.

Stripped all the mill scale off the tubing before I welded, to me it's far easier to strip before it's welded into a structure and I live in the desert so it won't rust during the build. I used to have all the stuff for this type of project but sold it off after years of little use. I'll be doing this with a minimal fab type tools.



The $50 stick welder was very capable in the right hands, I wish I had those hands.




I used 2.5" .180 wall for the 4' tongue.


Looks tiny but it takes up allot of space in the garage. Next on the to do list is the sides.

 

Progress continues.
Finished up the side framing, floor tabs, lights, fender mounting and started on the tent uprights.


I wanted strong fenders, trailer-fenders.com filled the bill.


The wiring is all secured to welded on tabs with stainless steel tie-wraps.


The tent uprights were a concern, the needed to be easily removable and I didn't want movement that would cause a rattling trailer going down the road so everything had to be bolted up solid. Most of the DIY trailer builds that raise and lower a RTT seem to have loose fitting telescopic setups that are heavily dependant on pinch bolts to try and keep them solid during transport. With that in mind the tent uprights slide into a tightly fitting upright tubing that's part of the trailer's frame. They fit tight and are bolted to the trailer frame with 1/2 hardware. To do this I rounded off the corners of some nuts and pressed them into drilled holes in the inner tubing, then welded them in place and finished it off by grinding them smooth. Each upright is secured with (2) 1/2" grade 8 bolts and each is strong enough on their own that you could tip the trailer over if one was strong enough.





I'll be attaching 6" planks to the sides and front to fill in the openings.

The bed will get covered by 4x8 marine ply.

Looks pretty small in the picture but it's an awkward piece of wood to move around.


Added a jack, chains and a handle for moving the trailer.


Next phase was the tailgate. It needed to be strong, easily opened and closed, preferably a slam type mechanism like a typical pickup. I wanted to use cable stays that allowed the tailgate to have 2 different open positions, using chains would be too noisy. One position for typical use and a lower position for when I'm loading a moto.


Typical position


Here it's in the moto loading position


Slam latch with added locating pins to prevent the trailer sides from bowing out.


My plan is to finished it off with some diamond plate that I'll attach with rivnuts.


Next project is building a height adjustable tent platform with gas strut assistance that doesn't rattle.

Stay tuned.

 

Progress update;



The tent platform is completed built along with system to raise and lower it.

Tool free configuration of the platform changes was something I wanted. Best solution was large hand nuts. To raise or lower the platform requires loosening the large front and rear hand nuts followed by pulling the two pop pins at ether end of the tents platform and that end slides quietly up to full extension taking about 4 seconds. I used a 50# strut at each corner which first appeared too stiff but after the tent was mounted and they got a little use they worked nicely. It requires about a 15# downward tug to lower ether end which is done in the same manner as elevating it, one end at a time. The slotted rear brackets on the platform allow the distance between the pivots to increase as ether end deviates away from the height of the other end. Whichever end is done first you pull the pop pins at the other end and the platform levels by itself, tighten the 4 hand nuts. The inner to outer telescopic pieces have a pretty tight clearance to avoid rattling, 1/16" between the 2 components, any more and they'll rattle w/o using pinch bolts which I want to avoid. It's just tight enough now that when it's locked at a height it's solid and quiet. I'll be cutting down the large wing nuts a little and adding nylock bolts behind them to prevent vibrating off during towing.



I figured making a 130# tent and platform raise and lower smoothly would be a challenge, any minor deviation in the sides of the trailer is amplified 2~3X at the top of an upright. I got the uprights pretty close to square but I did have to accommodate some deviation, I used 3/4" high misalignment hiems designed for A-arms. They're an excellent tight tolerance heavy duty pivot point that's super under stressed in this application. The high misalignment factor easily accommodates the slight deviations and pivots smoothly. They're overkill for this application but they were laying around and they worked well.


This is how I configured the lifting struts, pushing straight upwards directly below the platform's pivot points. Placing the two largest opposing forces on a similar plane makes the tubing more of a guide and eliminates the extra drag there is when it the slider is unevenly supported.


The trailer needed a spare tire mount, I didn't want to add any more weight to the tongue so it needed to be behind the rear axle. I'm not in love with the location so I made the mount removable in case I change my mind.


Now that the frame and mechanism was done it was time for the final test, Will the tent fit properly, can I raise and lower it easily? Will it rattle and/or is it wobbly. Time to see.



Deployed


The system works well, sliders, gas struts and pop pin locks work just as I'd hoped, no surprises with the extra weight applied. I'd have preferred better pop locks but all those small parts really add up, I chose the less expensive locks. When shaking the framework it there's still no rattles and it feels solid, the whole trailer is moving and I don't feel any flex. The only sway is the suspension slightly flexing the springs and it's minimal. I'll see if that changes any once it's drug 50 mi down a desert road.

I climbed in an once inside you can't tell it's not mounted on the rack of a truck, very minimal rock n roll. The suspension is way under loaded which helps but parked on a level spot I can easily sleep in it just hitched to the truck w/o stabilizer jacks which also tells me the suspension is really stiff. I may have to address that. Aside from paint and putting the wood on it's completed. If you made it this far thanks for checking the build out.

 

Moving on: the RTT framework is complete and paint was next. Since all the mill scale was already stripped off the tubing prepping for paint was pretty easy. It got a coat of brushed on red oxide primer followed by a couple coats of brushed on Rustoleum Gun Metal Hammercoat. I liked the look of the bare metal during the build so I stuck with the look. I chose Rustolem's Hammercoat textured finish because it's easy to touch up with a brush and is mostly undetectable once the paint dries. Spraying would have given a smoother finish but I wanted a brush on finish with all the metalwork since this is also a utility trailer and will get likely get scratched up some.

The paint work is in the rearview mirror and I moved on the trailer floor. I used a 4x8 sheet of marine ply with a couple coats of marine poly for protection. There's (20) 7/16" carriage bolts holding it down, the bed is stout.



I didn't want to use common pine for the side planks, too many knots plus they're usally wet and tend to warp, I found some select New Zealand pine that has no knots and is kiln dried. It got bolted on to the tabs with SS hardware.


I'm pleased with the way the tailgate turned out although I'm not a big fan of the latches I used but they allow it to slam latch like a typical pickup's tailgate.

The planks didn't fill the openings completely, I left the larger gap near the top so the railing can be used as a grab handle.

Spare tire looks huge up in that position but it mitigates some tongue weight.


Fenders cot sprayed with darker shade of hammer coat and non-skid panels added to the top for standing.


Added a little bling to the fender steps.


All the lights were put back on and I took it to get weighted, then to the DMV for inspection for tagging. Since it's a "utility" trailer under 3K# it gets a permanent tag. The trailer weights 600# as it sits in the pic w/ no tent or it's platform. Those parts will add another 140# to the trailer.


Now that it's tagged all that's left putting the platform and RTT back on.

I haven't pulled it much yet and set the tire pressure to 30psi for now to see how it rides and in the configuration above (utility/empty) I can't tell I'm pulling a trailer. Sizewise it pretty much hides behind the tacoma when straight and isn't obvious in the mirrors, the spare tire sticking up actually helps in that regard, esp backing.

 

I was able to finish up the project today and do some pull testing. Rides like I expected with no drama. The wind resistance is noticeable hauling with the tent is at the upper position, at that level it sits about 2" higher then it would bolted to the topper on a tacoma that had a 2" lift. The tent platform has to be lowered to fit past my garage door and it's high enough in the lower position to fit bicycles below the tent. It has to be raised up half way to fit my motorcycle under the tent. There's 8" of elevation travel with 4 selectable positions.





Elevated position


I'm pretty satisfied, the build met my goals and there's not much I'd do differently if I was doing it again.

 

Desert Test Drive

 

I got in some highway testing in with the new trailer/camper setup,

My truck gets 20~21mpg at highway speeds (70-75mph), pulling the trailer I'm getting 17mpg. Loaded = 270# motorcycle, 110# of liquids (fuel/water and all the camping/riding gear. Avg speed is a little less since I'm easing up on the hills more than I would otherwise. The truck's typical coolant temps were 186F with a +4 degree swing on longer climbs, pulling the trailer the new base is 190F with the same +4 degree swing when climbing.



Camping wise I slept very well in the tent using a diesel heater, the overnight temps dropped to 32F and I could have used bedding to stay warm enough but I wanted to give the heater a multi day workout. It did great keeping everything warm, too good even on low. Inside temps would be too hot until it got to the low 30s but I cracked open a couple tent windows and that made it comfortable. I wasn't able to use the awning due to some extremely high winds (gusts over 60mph). In poor weather the setup leaves a little to be desired, no good place to get out of the wind to prepare and cook food but the sleeping isn't affected.

Despite some pretty high winds during the drive the trailer did great. The extra drag on the motor was noticeable whenever the trailer is being pulled but the wind conditions didn't affect it near as much as I expected. With the bike loaded backwards the tent can be lowered to it's lowest position which helps allot. In that configuration I suspect much of the headwinds blow right over the trailer and any crosswinds blow through the trailer. It was zero drama pulling it despite the wind, easy enough that I'd forget it was back there.

 

( . )( . ) awesome build! looking to do something very similar this summer. Thanks for the pics!!