Introduction: Bicycle Sidecar for Your Dog

About: My name is Travis and I like to build cool stuff!

The inspiration for this project came from stevebod and the bicycle sidecar he built:

After seeing stevebod's build, I immediately became intrigued and knew I had to build one for myself. There was only one problem: I don't have a child to ride in my sidecar. I do, however, have a dog named Dewey who would love to go on bike rides to the dog park. So with this solution, I began building my sidecar!

I built mine to be adjustable and pivot like stevebod's design but mine isn't exactly the same. I didn't need to make mine as sturdy as his because mine would only hold a 15lb dog, not a child. I also wanted mine to be able to be quickly attached and detached without the use of a wrench. I also had the goal of building it without welding mainly because I don't have the supplies for welding and I don't want welding to intimidate people who want to build this. So with that, let's get to it!

If you like this and want to learn more or see what other things I'm up to check out my website at

Step 1: What You'll Need

Supplies You'll Need:

  • Metal
    • (18") of 2"x1" rectangular aluminum
    • (64") of L-shaped aluminum
    • (4") of thick 2" wide steel strip
    • (12") of 1" wide aluminum strip
  • JB kwikweld
  • Black Plasti Dip (can also be bought at home depot)
  • (2) J-bolt style Gate Hinges (I got mine at Home Depot)
  • 16" Bicycle Wheel
  • Wood
    • 1/4" plywood
    • the thinnest plywood you can find
    • 1/2" plywood
    • 1x2 lumber
    • 1x3 lumber
  • Hardware
    • 1/2" long lath screws
    • (2) Cotter pins appropriate for a 1/2" shaft
    • (8) [3/8" x 1-1/2"] bolts with appropriate lock washers and nuts
    • (6) [3/8" x 2-1/2"] bolts with appropriate lock washers and nuts
    • (2) [1/4" x 1-1/2"] bolts with appropriate lock washers and nuts
  • Gray spray primer
  • Flat black spray paint
  • (1 quart) flat paint for your sidecar
  • (13" x 28") 3" thick cushion foam (I got mine at a local upholstery supply shop)
  • (1 yard) vinyl faux leather (I got mine at a local upholstery supply shop)
  • (8') 3/4" polypropylene strap
  • (2) 3/4" metal bolt snaps
  • (2) 3/4" metal slides

*Before we begin I would like to note that I have written this instructable in the most logical order in which you should build this sidecar. However because it was my first time building this sidecar, I didn't build it in the most logical order. So you may notice some things are painted or finished in photos before we have even gotten to that step. This is because I have reordered everything to make it as logical and easy as possible for you.

Step 2: Hardware for the Bike

First you will need to build the hardware that will attach to your bike.

Begin by cutting an 8" piece and a 10" piece from your rectangular aluminum with a hacksaw. The 8" long aluminum will be your vertical piece that attaches to your bike. Drill a hole through one side about 1/2" from the end that is big enough to fit on your bike's rear axel. To add reinforcement, drill a hole in the same place on your 4" long thick strip of steel and use JB kwikweld to secure it to the back of your rectangular aluminum. Then switching to the other end of the 8" piece, drill (4) 3/8" holes, 1" apart, through both sides of the rectangular aluminum.

Moving on to the 10" long aluminum, this will be the horizontal piece which holds the gate hinges. Drill (2) 3/8" holes 1" apart on top of each other in the middle of the 10" aluminum piece. Next, place your gate hinges at each end of the 10" piece. Use these as a guide to drill 3/8" holes to mount your gate hinges to the 10" aluminum piece.

You can now mount your gate hinges onto the rectangular aluminum piece using (4) [3/8" x 1-1/2"] bolts with appropriate lock washers and nuts.

You can also mount your 10" horizontal piece to your 8" vertical piece of aluminum using (2) [3/8" x 2-1/2"] bolts with appropriate lock washers and nuts. Now because you drilled (4) holes in your vertical piece of aluminum, you can adjust the height of your horizontal piece so your sidecar sits flat with your bike. You won't exactly know what height is ideal yet but you can always adjust it later.

Next you can attach your vertical piece to your bike's rear axel using the existing nut and washer from your bike.

I realize that this description is very wordy so hopefully the photos will be of more assistance. If you have any questions about this process, please feel free to ask.

If you like this and want to learn more or see what other things I'm up to check out my website at

Step 3: Frame for the Sidecar

Cut (2) 20" pieces and (2) 12" pieces from your L-shaped aluminum using a hacksaw. Lay down the 20" pieces and place the 12" pieces on top using an L-ruler to make sure your angles are 90 degrees.

You can weld the frame together or bolt it and use JB kwikweld which is what I opted to do. This works great and is plenty strong for my purposes.

Mix up your JB kwikweld, apply it to each corner of your frame, and let it dry completely. Then drill a 3/8" hole in each corner and use [3/8" x 1-1/2"] bolts with appropriate lock washers and nuts to bolt it all together.

You should now have a sturdy frame for your sidecar!

Step 4: Plasti Dip the Hardware and Frame

This is optional but I feel it gives the sidecar a very nice, professional look. I chose to spray the entire frame and hardware for the bike with black Plasti Dip. This creates a durable, rubberized finish on the frame that looks almost like powder coating. I'm sure you could also use a black spray paint but it may not be as durable.

If you like this and want to learn more or see what other things I'm up to check out my website at

Step 5: Construct the Frame for the Body

Next we will begin work on the body of our sidecar by cutting the top and bottom pieces of your sidecar. Begin by marking a 13" x 32" rectangle on your 1/4" plywood. Then find the centerline and draw your curve for the front of your sidecar as evenly as possible. Use a jigsaw to cut out the shape you just drew; this will be the bottom of your sidecar. Now use your bottom piece to trace the top piece of your sidecar and cut that out.

Next, cut (3) 16" pieces of 1x2 lumber to act as your supports between the top and bottom pieces. Drill and screw in the 1x2's into your bottom piece of plywood. Put one at the tip of your sidecar and the other two 5" from the back of your sidecar on each side (See photo above). Now to put the top piece on, place a bead of glue on the end of each 1x2 and align your top piece of plywood with a 5" offset. Use a nail gun to shoot a nail through the top into each 1x2.

You should now be able to see the basic shape of your sidecar coming together!

Step 6: Construct the Back and Trunk

Now moving on to the boot of your sidecar. Begin by cutting a 1x3 piece of lumber to a length of 13". Use your nail gun to nail this to the very back of your bottom piece of plywood (see photo).

Measure the distance between the top of the 1x3 and the back end of the top piece of plywood. Cut a rectangle from your 1/4" plywood that is the length you just measured and 13" wide. Also cut a hole in this rectangle which will act as the trunk of your sidecar. And while you've got the jigsaw out, cut the trunk lid 3/4" bigger on each side than the hole you cut for your trunk.

Now to attach the back piece of your sidecar place a bead of glue on the top of the 1x3 and the back end of the top piece of plywood. Place your back piece on your sidecar and let the glue dry. Also use the nail gun to additionally secure your back piece.

If you like this and want to learn more or see what other things I'm up to check out my website at

Step 7: Reinforce the Body to Hold the Plywood Skin

Next, we need to add some reinforcement to screw your plywood skin in to.

Cut 1x2 pieces of lumber to surround your bottom piece of plywood that is straight. Use the nail gun to nail these pieces in through the bottom of your sidecar.

To reinforce the curved parts of your sidecar we will use 1/2" thick plywood. Trace the shape of the top and bottom of your sidecar onto the 1/2" plywood and cut these out. You can then continue to cut them so they are about 3" wide to reduce the weight of your sidecar. Also cut the bottom piece of 1/2" plywood to avoid the 1x2 at the front of your sidecar. (see photos)

Glue these pieces on using clamps to ensure a solid structure, and let them dry completely.

After these reinforcement pieces have dried it is a good idea to cut an angle on the top and bottom piece of the front so the plywood skin will sit better. Angle your jigsaw and go around both front edges to achieve this.

Step 8: Add Straps to Hold a Dog

Now is the time you'll want to attach the straps that will hold in your dog. I opted to put one coming from the top back of my sidecar to attach to my dogs chest harness. I also decided to put one coming from the bottom front of my sidecar to attach to my dogs collar. This way I will be able to adjust the length of the straps and allow my dog to stay sitting up or laying down in the sidecar.

For the top back strap, cut a 1x2 to a length of 11-1/2". This will fit in between the two support 1x2's in your sidecar. Paint this 1x2 piece black to match your interior. Drill and screw in a 3' long piece of strap (using a washer) to the center of your 11-1/2" 1x2. Wrap the strap around the 1x2 a few times and use your nail gun to nail this between the two support 1x2's (see photos).

Now for the bottom front strap, cut a 1x2 to a length of 4" and paint this black as well. Attach a 5' long piece of strap the same way you did for the back strap and nail it into the front inside your sidecar.

If you like this and want to learn more or see what other things I'm up to check out my website at

Step 9: Attach the Plywood Skins

Now for the fun stuff: attaching the plywood skin to your sidecar! This part can be a little tricky but it definitely gives an awesome finish and look to your sidecar so it's worth it!

First cut your thin plywood into roughly 24" x 45" rectangles. This is larger than they need to be but you can trim them later. You'll need to soak your plywood in warm water for a few minutes so it can bend without cracking.

Begin by placing a bead of glue on every edge on the side of your sidecar. Align your thin plywood and begin screwing in your skin. I used lath screws to create a look almost like rivets and placed them 4" apart. Use a ruler to help you with the distance from the side of where to put the screws so you don't miss the frame to screw in to. Start at the back and keep working your way down, switching sides for every other screw. It helps to have a second person to help hold the skin in place. Continue until the skin is completely screwed in all the way to the front.

Now you'll need to trim the extra plywood from the sides. I found that using a utility knife was easiest and provided the best finish. Slowly drag your blade along the edge of the sidecar, doing this as many times as possible to cut through the plywood. Use a straight edge at the front of your sidecar to achieve a nice line.

Repeat this exactly the same way for the other side and you should now really be able to see your sidecar forming!

Step 10: Secure the Front

To join your plywood sides together at the front, use metal flashing to get a nice finish.

Begin by gluing 1x2’s (painted black) on the inside of each sidewall to give you something solid to screw your flashing into. Next cut your flashing a little longer than needed to provide you some room for error. Mark drill holes every 2” on each side of your flashing so you know where to put your screws. It helps to have someone press the flashing down while you work your way down on each side screwing the flashing onto your sidecar. After it is applied you can use tin snips to make a more accurate cut on the top and the bottom.

If you like this and want to learn more or see what other things I'm up to check out my website at

Step 11: Cut the Top Opening

Now you’ll need to cut the opening in the top piece of plywood of your sidecar using your jigsaw.

Next, you’ll need to reinforce the sidewalls where they are open and cut them to your desired shape. Using ½” plywood, cut pieces that are equal in length to the top opening of your sidecar. Glue, clamp, and let these dry on the inside of your sidewalls to add strength.

Once those have solidly dried, you can use the jigsaw to cut your swoop down in the sidewalls.

Step 12: Add the Windshield

Prepare for your windshield by cutting a 1x2 to the width of your sidecar and ripping it to the angle you want your windshield to be. Attach this with glue and screws to your sidecar.

To get a windshield, I used an epilog laser to cut a clear piece of 1/4" acrylic. If you don't have access to an epilog laser, ask around and check the yellow pages or craigslist. If that fails, email me at and I can help you out.

If you like this and want to learn more or see what other things I'm up to check out my website at

Step 13: Finish Up the Frame and Test It Out

Now that you have the majority of your body finished, you can use it to help you finish the frame. Line up your body on your frame as desired and drill (4) 3/8” holes through the bottom of the body and through the frame.

Now you can line up where you want your wheel in relation to your sidecar body and drill a hole in the side of your frame.

You can also line up your frame in relation to the hardware on your bike. Drill (2) ½” holes in the opposite side of your frame where you want to attach your J-bolts.

I would also recommend using a drill press to drill a hole through the end of each gate hinge which will allow you to use a cotter pin to prevent the sidecar from slipping out of the hinges.

Now you can attach your wheel, attach your gate hinges, attach the body to the frame using [3/8" x 2-1/2"] bolts, and attach your sidecar to your bike and take it for a test ride!

After testing my sidecar, I found that I need a little more clearance when making left turns. So, as you can see in the photos, I used a coupling nut to extend the sidecar 3" farther out.

I also decided to add a second support bar off of the bike to prevent the sidecar from moving up and down like a seesaw (it sounds kinda fun to me but the dog didn't really like it). Use a strip of aluminum cut to the appropriate length so it reaches from the frame of the bike to the 10" horizontal cross piece of your bike hardware. Cut another strip of aluminum 2" in length to attach the longer aluminum strip to your bike frame. Use a bolt on each side of your bike frame to hold these two strips of aluminum together and wrap your bike frame in electrical tape to prevent scratching. Drill a hole on the opposite side of your aluminum strip to attach to the existing bolt on the bike hardware. Paint the aluminum with plasti-dip and secure all hardware on your bike. Please refer to the photos for assistance with this part.

Step 14: Finishing Work and Painting the Body

Now you should basically have your sidecar body build, all that’s left to do is some filling, sanding, priming and painting. Use wood filler to fill in all the edges of your sidecar and sand as necessary to get a smooth finish. Now you can also use flat black spray paint to paint the inside of your sidecar completely.

Now moving onto painting the exterior. Use masking tape and newspaper to cover the interior black part of your sidecar. Spray the entire exterior with gray primer.

After your primer has dried, you can move on to the fun part; painting on the color! I choose to get a quart of flat Army green color mixed up at Home Depot because I couldn’t find a spray paint that was the exact color I wanted. Use a combination of a small paint roller and a brush to cover your sidecar. I did 3 coats, which gave a great finish and don't forget to also paint your trunk lid.

If you like this and want to learn more or see what other things I'm up to check out my website at

Step 15: Upholstering the Interior

While your sidecar is drying, it is a good time to make the interior cushion for your sidecar. I used a 3" thick foam piece for my cushion.

Begin by cutting a piece of 1/4" plywood slightly smaller than the interior bottom of your sidecar. Cut your foam so it fits precisely around the entire interior of your sidecar. Glue the foam to your plywood.

Now, roll out your vinyl faux leather face down and trace the shape of your cushion making it considerably larger, allowing it to wrap around the edges and be stapled to the plywood. Now I do not possess any sort of upholstery skills so if I can do it you can do it. Wrap your vinyl tightly around the cushion and use a staple gun to staple it into the plywood.

Step 16: Final Touches

After your paint has fully dried, you can secure your sidecar to the frame. You'll also need to attach your trunk lid to the back using hinges, attach your windshield, and finish up your straps with the metal slides and metal bolt snaps. Also feel free to add a "I brake for poodles" bumper sticker, a custom license plate, or an "I'd rather be sniffing my butt" license plate frame. Be creative and have fun with this!

Step 17: Take It Out for a Spin

There you have it: a sidecar for your bicycle! Grab some doggles for your pooch and take it out for a spin! It took my dog, Dewey, about 5 minutes to sit in it comfortably. Then I slowly started pushing him around and soon we were off and riding. He now loves it and gets excited every time he sees it!

It is remarkably easy to ride. Turning is not a problem at all with the pivoting design; you know the sidecar is there but it doesn't inhibit riding whatsoever. And it can be attached and removed from the bike in seconds without the need of any tools.

Now all I need is a Form 1+ 3D printer to make a custom hood ornament of my dog for the sidecar!

Thank you to Stevebod for his original Instructable, couldn't have done it without that!

Please let me know if you have any questions, I would be happy to help. Have fun!


P.S. Don't forget the doggles!

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