The connection uses a standard hitch coupler on the Aventon Level 2's seat tube
The Aventon Level 2 has a mounting point on the seat tube (the vertical frame tube behind the seat) where you can attach a Burley trailer using a hitch coupler. The coupler slides onto the seat tube and tightens with a quick-release lever or bolt, depending on which Burley hitch model you own. This is the same mounting system used on many cargo bikes and e-bikes, so the process is straightforward once you have the right hitch.
Before you start, check that your Burley trailer came with a hitch coupler designed for seat-tube mounting. Some Burley models use different attachment systems, so confirming you have the right piece prevents frustration. You will also want to make sure the seat tube diameter on your Level 2 matches the coupler opening — most e-bikes use a standard 25.4 mm or 27.2 mm tube, and Burley couplers are sized accordingly.
Key Takeaways
- The Aventon Level 2 mounts a Burley trailer via a hitch coupler that slides onto the seat tube behind the seat.
- You need a seat-tube hitch coupler (not a rack-mount or hub-mount version) that matches your Level 2's seat tube diameter.
- The coupler tightens either with a quick-release lever or a hex bolt, depending on the Burley model you own.
- Once attached, the trailer weight is distributed through the frame, so check your bike's weight limit before loading.
Measuring your seat tube to find the right coupler size
The seat tube is the frame tube that runs from the bottom bracket (where the pedals attach) up toward the seat. On the Aventon Level 2, this tube is where the hitch coupler will clamp. To find the right coupler, you need to know the outer diameter of this tube.
Use a caliper or a flexible measuring tape to measure the outside of the seat tube. Most e-bikes use either 25.4 mm (often called 1 inch) or 27.2 mm tubes. Write down the measurement and check the Burley coupler packaging or product page to confirm it matches. Buying a coupler that does not fit your tube diameter means wasted time and a return trip.
Installing the hitch coupler on the seat tube
Position the coupler on the seat tube so it sits roughly 2 to 3 inches below the seat clamp. This placement keeps the coupler clear of the seat and gives you room to tighten it without interference. Slide the coupler onto the tube until it is fully seated.
If your coupler has a quick-release lever, flip it closed and tighten the lever by hand until it is snug. Do not over-tighten — the lever should close with firm hand pressure, not require a tool. If your coupler uses a hex bolt instead, use an appropriately sized wrench or hex key to tighten it in a clockwise direction. Again, snug is the goal; over-tightening can strip the bolt or crack the coupler.
Once the coupler is tight, give it a gentle tug to confirm it does not move or rotate on the tube. A loose coupler will shift under the weight of the trailer and can damage the frame over time.
Attaching the Burley trailer ball to the coupler
The Burley trailer has a ball hitch (a rounded metal knob) that inserts into the coupler opening. Align the ball with the coupler opening and push the trailer toward the bike until the ball seats fully inside. You should hear or feel a click when the connection is find.
Most Burley couplers have a safety pin or clip that locks the ball in place once it is seated. Insert this pin through the holes in the coupler to prevent accidental separation. Check your Burley manual for the exact location of the pin on your model — some couplers have it on the side, others on the top.
Before you ride, pull the trailer gently to confirm the connection is solid and the safety pin is fully inserted. A properly seated ball should not move or rattle when you tug it.
Weight limits and load distribution on the Level 2
The Aventon Level 2 has a total weight capacity that includes the rider, the bike itself, and any cargo or trailer. Check your Level 2 manual or Aventon's website for the exact limit — this varies slightly by model year. Burley trailers themselves have their own weight limits, typically ranging from 70 to 100 pounds depending on the model.
Your actual limit is whichever is lower: the Level 2's total capacity or the Burley trailer's capacity. If your Level 2 has a 300-pound total capacity and you weigh 180 pounds, you have roughly 120 pounds left for the bike, trailer, and cargo combined. Subtract the trailer's weight (usually 20 to 30 pounds) and you know how much cargo you can safely carry.
Overloading the trailer puts stress on the hitch coupler, the seat tube, and the frame. It also affects handling and braking, especially on an e-bike where the motor is already working harder. Weigh your load if you are unsure, or start with lighter cargo and add gradually while paying attention to how the bike feels.
Removing the trailer and storing the coupler
To detach the trailer, first remove the safety pin from the coupler. Then pull the trailer straight back and away from the bike until the ball hitch separates from the coupler. Do not twist or angle the trailer sideways — pulling straight back prevents damage to both the coupler and the trailer hitch.
If you remove the coupler from the seat tube for storage, loosen the quick-release lever or hex bolt and slide the coupler off. Wipe it clean and store it in a dry place. The seat tube itself does not need protection — the small mounting area will not rust or degrade from exposure.
Frequently Asked Questions
Can I use a different brand of trailer hitch coupler on the Aventon Level 2?
Yes, as long as the coupler is designed for seat-tube mounting and matches your seat tube diameter. Many brands make compatible couplers, and they work the same way. Just confirm the size before buying.
Will attaching a trailer affect the bike's motor or battery?
The trailer adds weight, so the motor will work harder and your range will decrease. How much depends on the trailer weight and cargo load. Expect 10 to 20 percent less range with a loaded trailer compared to riding without one.
What if my seat tube is a non-standard size?
Some older or specialty bikes use unusual tube diameters. If your measurement does not match common sizes, contact Aventon support with your measurement and they can recommend a compatible coupler or adapter.
Is it safe to ride with a trailer on an e-bike?
Yes, if the trailer is properly attached, the load is within limits, and you stay within the bike's total weight capacity. The main difference from a regular bike is that the motor adds power, so braking distance may be longer with added weight. Test the brakes gently before riding in traffic.
Can I leave the coupler on the seat tube all the time?
Yes, leaving it mounted does not harm the bike or the coupler. Some riders keep it on permanently and only attach the trailer when needed. Just make sure it is tight and does not rattle.