| Axle coupling: |
|
| Seatpost coupling: |
|
| Frame coupling: |
|
| Quick-release axle: |
|
| Thru-axle: |
|
Before buying an e-bike and bicycle trailer there are a few important points to keep in mind so that your child travels safely. First you should check the manufacturer's approval, since not all bicycles are suitable for trailers .
Carbon frames in particular can break under the additional load. So make sure your bicycle offers the stability needed for towing a trailer.
Important:
Trailers must comply with DIN standard EN 15918 in order to ensure safety standards such as coupler stability and spoke protection.
Also pay attention to the weight limits of your e-bike and the bicycle trailer. Do not exceed either the maximum towing load or the permissible total load of the bicycle, in order to ensure safety while riding. Tip: When transporting a baby, the right baby insert in the bicycle trailer is crucial for your child's comfort during the ride. With a seat reducer, a baby shell or hammock even newborns can be transported in the bicycle trailer.
In most cases the bicycle trailer is attached to the rear axle of the bike . There are various types of axles, which are presented in the following. After you have determined the axle type of your e-bike , you can then mount the matching bicycle trailer coupling.
Good to know: There are also other attachment points for the bicycle trailer that require other couplings. These are for example the seatpost coupling (attached under the saddle ) or frame coupling (mounted with drilled holes or at corresponding attachment points on the bike frame).
Each axle requires specific attachment methods for your bicycle trailer. The axle type determines which coupling is suitable and how it must be mounted.
The rear axle is particularly well suited for mounting a trailer, since thanks to its low center of gravity it offers high stability during the ride. Important: The bicycle trailer is always mounted on the left in the direction of travel. This ensures sufficient distance to the chain and the derailleur.
The quick-release is a common type of attachment, which is particularly suitable for mounting bicycle trailers.
1. Open the quick-release:
Open the lever
to release the axle. The quick-release has two
small springs at the ends and an axle diameter of about 5 mm.
2. Mount the coupling:
Slide the
coupling adapter onto the axle and place the coupling at the
desired position. Tighten the screw bolts hand-tight to create a
stable connection.
3. Fix:
Close the lever until it sits tight. Make sure not to close it with force, so no damage occurs.
4. With insufficient threading:
If the thread
is too short, you can use a longer quick-release axle.
Remove the old axle and replace it. Make sure not to lose the springs
.
1. Prepare mounting:
Check whether your thru-axle has the required diameter of at least 9 mm and a thread on one side.
2. Use adapter:
In many cases the
thru-axle requires an adapter to correctly mount the coupling.
Make sure the adapter is compatible with your e-bike.
3. Use torque wrench:
Mount the
coupling according to manufacturer specifications and tighten it with a
torque wrench. This ensures the correct tightening force
and stabilizes the mount.
4. Adjustment and fixation:
Make sure the coupling is correctly aligned and securely attached to ensure a smooth ride.
1. Check the axle:
Make sure that enough
thread is available for the coupling (at least 15 mm). Full axles
are typically recognizable by cap nut attachments and cannot
be removed.
2. Use adapter:
If the thread is too short
, an adapter may be necessary, e.g. a 3.8 mm or 5 mm thick
axle adapter. This ensures that the coupling can be safely mounted
.
3. Ensure stability:
Make sure the coupling sits tight and check that no parts feel loose.
When attaching a bicycle trailer to the e-bike, there are various options that depend on the axle and the e-bike model.
The axle coupling is mounted directly to the rear-wheel axle or the frame of your e-bike. This system is ideal for child and cargo trailers, since it offers a particularly stable connection.
The axle coupling impresses with its fast mounting and its versatility for different trailer types. Particularly with frame locks and special coupling systems it is securely and easily attached in just a few steps.
Tip: Make sure the coupling system sits firmly and does not obstruct moving parts like brakes or spokes.
This coupler attaches below the saddle and is particularly suitable for bicycle trailers fitted with a push or pull handle. Ideal for lighter trailers or short distances.
Important: Do not max out the payload, since the weight acts higher up on the bicycle frame and can increase the risk of tipping.
Frame couplings are a popular choice when your e-bike already has drill holes or attachment points on the frame. They are often mounted on the chainstay.
Some e-bikes with large batteries or special frame designs require an extended axle to securely attach the coupling. This is because the distance between the axle and the frame must be enlarged to create space for the coupling.
Here you can use adapters or special axle systems, that enlarge the required distance and enable a secure connection . Make sure the extended axle is compatible with your e-bike model, to ensure stability and safety during the ride.
This option is particularly recommended if you want to safely and reliably attach cargo trailers or heavily loaded child bicycle trailers to the e-bike .Once the axle type has been determined and the matching coupler correctly fitted to the e-bike, the last step follows: hitching the bicycle trailer securely. A careful connection ensures not only stability but also maximum safety while riding.
Here is a step-by-step guide to attaching the bicycle trailer:
1. Insert the tow bar into the coupler:
Carefully
insert the trailer's tow bar into the coupler. Make
sure it is seated correctly to ensure a secure connection between
trailer and bicycle.
2. Fit the safety pin:
Once
the tow bar is in the coupler, fit the safety pin to
secure the tow bar. The pin prevents the tow bar from
coming loose unintentionally while riding.
3. Attach the safety strap to the bicycle frame:
Attach
the safety strap to the bicycle frame for additional safety.
Make sure the strap is neither too loose nor
too tight. Too much tension could hinder steering
movements, while a strap that is too loose reduces stability.
4. Avoid contact with moving parts:
Make
sure that the safety strap and the tow bar do not touch any moving
parts such as the disc brake. This could cause problems with
braking performance or steering.
With these simple steps you can make sure your bicycle trailer is properly attached and that you can enjoy a safe ride.
Tip: A coupler anti-rotation device ensures that the coupler does not twist or come loose unintentionally while riding. It guarantees a stable and secure attachment of the trailer to the e-bike, even on demanding bends, at higher speeds or on uneven terrain.Last updated: August 6, 2026
Besides fitting everything correctly, you should also know the legal framework before heading out with a trailer on your e-bike:
Important: This information is for guidance only and does not replace legal advice – when in doubt it is worth checking the StVZO or asking your specialist dealer.
To keep your child safe, the coupler should not only be securely fitted but also come with the right safety features:
"You can tell a good coupler not just by the brand but by the details – an anti-rotation device, a safety pin and an additional tether are therefore standard on our systems, not optional." — Wilhelm Wenzel,
Head of Development at Qeridoo |
|
Universal couplers – often also called quick-release couplers – are compatible with many types of bicycle and a popular choice if you want to stay flexible. When buying, look out for the following:
That depends on the axle type of the e-bike. For quick-release axles there are specific axle couplers that can be fitted in a few steps. Modern e-bikes with thru axles often need an adapter that is fastened with a torque wrench. On older models with solid axles, polygon adapters or special axle adapters are the right choice.
First open the quick-release lever to free the axle. Then slide the coupling adapter onto the axle and place it in the desired position. Tighten the bolts hand-tight and close the quick-release lever until it sits firmly – do not force it shut. If the thread is too short, a longer quick-release axle can be fitted as a replacement.
In most cases a thru axle requires a compatible adapter – for example the Qeridoo thru-axle adapter – as well as a torque wrench for the correct tightening force. What matters is that the adapter is compatible with the e-bike model and that the coupler is correctly aligned after fitting, in order to ensure a safe and smooth ride.
Yes, the bicycle connection coupler for bike stands can be attached to frames with a KSA 18 standard (18 mm hole spacing). Alternatively the polygon adapter Giant M10 x 1.5 (KUFA system) or Giant adapter M10 x 1.5 (becco system) can be fitted to a trailer mount on bicycles of the brands Giant, Liv and Momentum.
These types of coupler provide a stable connection and are particularly suitable for e-bikes with fixed mounting points. With sensitive frame materials such as aluminum or carbon, care must be taken to protect the frame.
An anti-rotation device prevents the coupler from twisting or coming loose unintentionally during the ride – an important safety element especially on bends, at higher speeds or on uneven terrain. It is recommended for anyone who is regularly out with a bicycle trailer and wants maximum connection security.
First the manufacturer's approval of the e-bike for trailer operation should be checked – not all bikes are designed for it. Carbon frames can break under the additional load and are generally not suitable for trailers. The trailer must also comply with the DIN standard EN 15918, and the weight limits of the e-bike – both towing capacity and permissible total load – must not be exceeded.
After fitting, check all screws and attachment points for a firm seat, make sure that no moving parts touch each other, and take a short test ride on quiet ground. Watch out for unusual noises, wobbling or restricted steering. Before every outing the coupler should be briefly checked for firmness and, where fitted, the safety pin checked for correct seating.
A universal coupler, often also called a quick-release coupler, is compatible with many types of bicycle. When buying, you should look for compatibility with your axle type, a TÜV or GS seal and explicit approval for e-bikes.
With a trailer your e-bike may travel at a maximum of 25 km/h, the rider must be at least 16 years old, and the trailer should comply with the DIN standard EN 15918. Weight limits also apply, as does a requirement for lighting and reflectors.
