Introduction: Bike Rim Crab Trap

About: Technologist

Some time ago I met a guide who had some crab traps made from bike rims, they worked a treat, so I had my eyes open for some old bike rims on the road for some time. I found some! Hoping this instructable will help save some more bike parts from the trash as they are a great base for a solid crab trap.

This trap works well from a boat or the dock, but please note this trap does need to be checked frequently (5-15 minutes) depending on the number of crabs in the area, or they will consume ALL of the bait and leave.

Bringing a trap like this to a dock to try some catch and release with the local crabs can be great fun for the kids, the crabs get some good eats, the kids get a show. Win-Win :)

Parts to acquire (hopefully found):

  • Larger bike rims (equal or larger than ~57cm / 24" if possible)
  • Smaller bike rim (~30cm / 12")
  • Strong netting (pref. larger than the rim)
  • Thin utility cord < 3mm (must be able to fit between spoke holes)
  • Heavy cord of some poly variety suitable for crabbing (enough length for the depth of water you plan to fish)
  • Spray paint primer / anti-rust (optional)
  • Zip ties (optional)
  • Raw fish or chicken meat for bait

Tools needed / recommended:

  • Utility knife
  • Some thick gloves for handling crabs ( if you're a noob :p )

Time: 1 - 3 hours

Step 1: Prime the Rim / Cut the Net

If you have some primer / anti-rust paint, it is easiest applied first. Depending on the rim material, it may be difficult to find a paint which will stick nicely, but there is a paint out there for everything :)

Lay the netting in a large area and just cut so the rim can be centered nicely. You'll want a fair amount (30cm / 12") of excess on the sides, particularly if you'll use the net to tie (more on this later). The extra netting will also serve to expand as the trap is pulled, making it more effective to retain the catch.

Step 2: Attach It to the Rim

NOTE: If you like, the whole rim could be affixed using zip ties quite easily. If you want a bit more natural and less wasteful method, please consider the rest of this step, which worked well for me.

With the rim centered on equally spaced netting, cut 2 squares deep on one side. Then take the cut ends and push them through each of two of the nearest spoke holes from the inside of the rim. With one side, pull it through far enough to wrap it twice within the square portion from the net coming from the other hole. Pull each carefully back through the inside of the rim, ensuring that the knot from the netting catches with the other side. Pulling this should eliminate any slack and basically lock it to the rim.

Continue with this process on the opposite side of the rim, continuing in this manner such that the spacing of the netting is maintained as closely as possible around the rim. Some gaps are OK, but the net should be anchored with at least all of the spoke holes.

Step 3: Add the Little Guy / If You Save the Spokes

I just put this one in with zip ties, but you could use some utility cord. Just wrap it around and secure it to the middle of the netting of the larger rim. In addition, if you have some extra netting, you can add it to this little rim, to provide a bait holder feature. I don't suggest using the spokes for anchoring this to the net, as the metal could damage the netting, however, a spoke could work as a pin to clasp the bait holder shut.

Step 4: Drawstring

Using some thinner utility cord (needs to fit through the spoke holes), thread if through a spoke hole and loop it through one of the nearby net ties or zip ties.

Wrap the end around itself 3-4 times, then pull it through the loop (clinch knot).

Pull both ends of the cord and try to leave about 3cm / 1" of line at the end of the knot.

Pull the cord from the inside of the rim, if the knot worked out, it should lock without coming out of the spoke hole, if not, try again with a piece of net or zip tie further from the entry point.


While holding the cord on the exact opposite side of the rim, eyeball the cord at this stage so you have about 30cm / 12" of height when it is held up from the center (Not sure if there is a magic number here, it needs enough room to float away from the bait a bit, while not being so much that it tangles itself and the crabs etc.).

When you are happy with the length, cut the cord and tie it in a similar manner to the opposite side (or better yet, try to get the side to the left or right of this point)


Repeat the process on the other edges, so you have an anchor on at least 4 points.

Step 5: Wrap It Up / Go Crabbing

Tie the thicker poly cord to the thinner cord in a manner that the trap will hang evenly (near the mid-point). I just used another clinch knot (looped it around the two thinner cords, and around itself a few times and back through the loop).

Remember most areas will require a fishing license to retain crab, and there may be size and additional restrictions as well (do your research and learn more about what you are catching, as there are so many varieties. My experience is mostly with Dungeness and Red Rock crabs, where we keep male crabs only where the top of the shell from point to point measures no less than 6.5 " and 4.5" for the Red Rock variety. Some other varieties seem to do crazy things such as dropping claws and so forth, so please learn how to handle what you are catching.).

If you built the bait holder, you should be able to put the bait directly into this pocket, and then tie or wrap it up so the meat cannot be removed in one piece. Otherwise, tieing the bait in whatever means to the center area of the trap should work. This should be done just before dropping the trap into the water. If you are on a boat, people will typically use a float at the end of the line to identify where the trap is and a means to pull it up. From a dock, same idea, just swing the trap out to the desired location, and tie the end of the line to a railing or anchor point.

After some time (5-15 minutes is usually all that is needed if there are crabs in the area as crabs are VERY efficient at consuming and removing the meat, you do not want to leave the trap unattended for more than 15 minutes), pull the trap up (once you start pulling, pull hard and fast hand over hand to prevent any from escaping) and check it for crabs. Remove crabs, and repeat.

When handling crabs, they can typically be picked up from the very rear where the claws cannot reach. I do NOT recommend holding them by the hind legs as this can easily damage the legs. If you are uncomfortable or new in this area, consider wearing some thick gloves.

Note: Please remember, these are very important creatures for the marine ecosystem, are living creatures, and despite having a hard exoskeleton, they should still be handled with care and placed back in the water on release without damaging any of the crabs appendages. Respect the laws in your location, and this should be a sustainable fishery for all.

When you catch a keeper, it is wise with most species to keep it alive until you are ready to cook it, as some release toxins if not kept alive. I suggest taking some water from where the crab was caught, this will not only keep the crab at home in breathable salt-water, but can be reused in a pot for boiling. I suggest a large stock pot on a rolling boil with salt water, cooking one crab at a time such that the temperature does not decrease substantially as they are added. Other varieties may require additional pre-cooking prep, once again, please learn about what you are catching in your area as there are many differences.

Good luck!