Convert a Child Trailer to Cargo

Author: Liz Vos

Cargo bike trailers can double the groceries and triple the fun!

Grocery shopping is much more fun by bicycle. I avoid traffic and get front row parking at the store, and unloading at home is a breeze since I can pull right up to the door. Storage was the only issue – I had to stick to my list very carefully and sometimes choose between getting a gallon of orange juice and a 6-pack of seltzer.

A cargo bike trailer is a great way to haul a load of groceries or yard sale finds, but they run $150 or more. I went for the more budget-friendly and fun version: retrofitting an old kids’ trailer.

Getting Started

First, you’ll need to locate an old youth bike trailer. Mine was a hand-me-down – a neighbor found it on the side of the road and he passed it on to me.

I wasn’t sure how I wanted to convert it exactly, so I started using it as-is to get used to the concept. It was pretty effective even without a platform – I put a tub inside the child trailer, and just like that my grocery capacity tripled.

The Conversion Begins – Strip the Fabric

I mostly just wanted the base frame of the trailer, so I removed the fabric and frame. I kept the fabric for future projects, but sometimes on an old trailer the fabric is dry rotted and falling apart from sun exposure – and it just needs to get trashed.

Bare trailer with all fabric removed

Choosing Your Materials

I went with a simple flatbed design – a piece of plywood resting on the frame. I secured the plywood to the frame with with eye bolts. The eye bolts provided a way to hold the plywood onto the frame while also providing a place to connect bungee cords. The bungee cords or rachets straps can hold down a Rubbermaid bins – or even two stacked on each other. They can also be used to hold down other creative cargo loads.

This basic flatbed design leaves me with options. I can switch between a recycling bin, a Rubbermaid-type bin, or stick with just the platform if I need to haul another cabinet or these traffic-calming flex posts.

If you keep an eye out in apartment complex mail rooms, you may even come across an abandoned package delivery bag that will fit your trailer perfectly.

Liz’s converted cargo bike trailer hauling all sorts of stuff

Construction

We used a circular saw to slice up our plywood to fit the size of the metal frame. For this build, we intentionally let the plywood extend further in the back past the frame.

We drilled holes into the corner of the cutouts to make it a bit easier to cut out the slot using a circular saw.

We cut a bonus strip of plywood and used wood glue to affix it to the main platform so it can bear a little more weight. After gluing it in place, we added short wood screws to firmly attach the reinforcing rib to the plywood panel.

Fitting a piece of plywood to the cargo trailer frame

Flip your trailer right side up. Insert the eye bolts through the matched holes in the plywood and the metal frame and secure them in place with the bolts. You’ll want to use thread locking compound or locking washers to make sure the nuts don’t vibrate off while you’re riding.

You can put the eye bolts wherever it makes sense for your build and the things you’re planning to carry. Where do you want attachment points? There should be at least four bolts between the plywood flatbed and the frame.

To protect your flatbed cargo bike trailer from the elements, paint the wood with polyurethane or whatever. Get arty, put glitter on it, go wild.

Enjoy Your Bike Cargo Trailer!