The purpose of this hub is to give a general overview of bicycle trailers. It will be the perfect starting point for anyone looking to buy their first bike trailer. Here you will be able to find general information about the basic types and uses of bicycle trailers as well as components and links to more details, reviews, and purchasing information.

Two Wheel Trailers:

Two wheel trailers allow for a wider cargo bed and higher wieght and volume capacity. Two wheel trailers are best suited for paved and smooth dirt road surfaces. When used on narrow trails and uneven terrain, they can be quite cumbersome and have a tendency to flip when one wheel hits a protruding object. Two wheel trailers are used for a wide variety of loads. Smaller, lighter versions are excellent for touring, commuting and local errands. Large versions are suitable for towing large objects (like canoes or kayaks), heavy loads, or loads that require large cargo beds (like child, passenger and pet trailers).

One Wheel Trailer:

One wheel trailers have a much smaller cargo bed then two wheel trailers as well as a smaller weight and volume capacity. Single wheel trailers track behind the wheels of a bicycle. Aditionally, a single wheeled trailer does not rotate side-to-side in relation to the bicycle (It is not attached with a univeral joint as is a two wheeled trailer). These two factors make a single wheel trailer well suited for use on single track and in any rough condition because a single wheel trailer does not fall over or flip unless the bicycle does and the trailer will follow the bicycle wheels around rocks and dips. The small cargo bed and excellent handling make single wheel trailers a very good fit for the varied terrain of bike touring and off road biking. There narrow profile is appreciated for riding on crowded streets, going of curbs and riding on narrow shoulder.

Extrawheel:

The Extrawheel is a variant of the single wheel trailer. The difference being that a normal single wheel trailer has a small cargo bed in between the bike and the trailer's rear smaller wheel, the Extrawheel positions a normal size wheel directly behind the bikes rear wheel. The frame of the trailer generally has racks or cargo netting. Racks are suitable for mounting up to 4 panniers while cargo netting can be used to hold bags or waterproof dry bags. The large wheel of the Extrawheel does a great job of rolling over obstacles. The closer placement of the Extrawheel's wheel makes for a much shorter overall trailer. The Extrawheel also offers the ability to replace the front wheel of the bicycle in an emergency situations. These trailers are made in Poland and widely available in Europe. They are just starting to become know in the US through specialty trailer shops that do carry the Extrawheel.

Long Tail Bicycles:

Long tail bicycles, while technically not trailers, serve much the same purpose allowing for extra hauling capabilities. Instead of towing a hinged cart behind the bike, trailer bikes integrate the large rear cargo area into the frame of the bicycle. This large cargo area built into the rear of the bicycle frame is ideal for much large racks and packs to be attached. Often, long tail bikes have reinforced frames and wheels to accommodate the extra loads. While they boast a better center of gravity and more maneuverability, long tail bikes can take some getting used to.

Trailer Bikes:

Trailer bikes are basically one wheeled trailers designed specifically for human passengers. They have seats, handlebars, and pedals, turning the trailer plus bike into a version of a tandem. Trailer bikes are a great transition for children who are too old for riding in a bike child trailer but not old enough yet to keep up with their parents on a bicycle of their own.

General Cargo:

The majority of bike cargo trailers are designed for hauling smaller loads, generally loads below 100lbs. These types of load are either bike touring gear or loads typically carried locally such as groceries, misc shopping purchases, work stuff or any other bulky items that need to be transported with daily living. General Cago Bike Trailers tend to be smaller, single wheel trailers like, the bob trailer, extrawheel, or xtracycle. There are also two wheel variants like the immensely popular Burley Nomad.

Child Trailers:

Bike trailers for children are designed with padding harness and even somtimes shock absorbers to reduce jostling. Bike Child Trailers have outer metal tubing frames with reinforced beams to keep this special cargo safe. Croozer and Burley make some of the most popular child trailers. Many companies offer special kits to turn the trailers into joggers or strollers.

Pet Trailers:

Bicycle trailers for pets are very similar to child trailers with padding, covers, and reinforced beams, but usually with design modifications specifically for pets (for example, tailgate flaps that allow low entry for older pets).

Adult Passengers

The most common trailers for adult passengers are the trailer bikes mentioned above, but there are also rickshaw-like conveyances used as ambulances, taxis, etc.

Trailer Tents

These tend to be like regular cargo trailers, only with a tent somehow built into the cargo area. Trailer tents sacrifice versatility for the ability to have a better bed than a normal tent can give.

Canoe and Kayak

These trailers are designed specifically to carry long narrow boats, with particular attention paid to the load's balance and weight distribution.

Heavy Duty Cargo

Extra long or extra wide, these trailers are reinforced and carefully balanced to allow for maximum towing capability.

Frame:

• Metal: usually cromoly or aluminum alloy tubing, assembled by brazing, welding, or nuts and bolts.
• Plastic: Molded, hi-density plasic frames are sometimes utilized ussually with metal sleaves or bolted on metal parts for interfacing with moving parts.
• Wood: seldom seen but sometimes used in make-shift and home-built trailers, fastened with glue, nails, screws, bolts, or a combination thereof. An example is here, another here bamboo and other improvised materials here

Axle:

Most two wheel trailers have a separate axle for each wheel, like those used on a bicycle. These separate axles usually mount directly on the frame using either threaded nuts, or a quick-release mechanism, or a press fit arrangement similar to wheelchair style hubs. The use of separate axles for two-wheel trailers allows the load carrying area to be between the wheels with its base below the axles, so as to keep the centre of gravity relatively low.

Some trailers support a normal axle on two sides, others mount the wheel off one side with a stub axle (a one sided axle).

Wheel

• Traditional spoked bicycle wheel in various sizes. Has the advantage of being light, strong, readily available. Pneumatic tires provide some suspension for the load, larger diameters ride smoothly and have much less drag than many other types of wheels.
• Solid metal wheels with solid treads, such as dolly wheels. Extremely durable but rough riding and usually slow due to small diameter.

Fender/Mud Guard:

If included, the fender helps to protect the cargo and the towing bicycle from road spray and dirt. One wheel trailers generally have a fender as the wheel is in line with the cargo. Fenders are not very common on two wheel trailers as the wheels are off-set from the cargo. On heavy-duty trailers, the fender may be designed to be capable of bearing heavy loads.

Hitch

Single-wheel trailers generally use a special frame hitch which attaches to both sides of the rear axle, and which incorporates a vertical hinge to allow cornering.

Two-wheel trailers must incorporate some form of universal joint or flexible coupling (e.g. rubber tube), both to allow cornering and to allow the bicycle to lean while the trailer remains upright. Since such couplings must have some slack in order to function at all, there is the possibility of resonance at certain pedalling speeds and trailer loads, especially in higher gears; the effect is that the trailer feels as if it is 'bumping' the bicycle - the simplest remedies are either to slow down or to pedal faster in a lower gear.

Two-wheel trailers which attach to the rear axle or chainstay generally have an angled towbar to help keep the trailer more or less centrally behind the bicycle. Trailers tend to have less effect on bicycle handling when hitched at the rear axle or chainstay, since this low attachment point doesn't push the bicycle sideways as much as a higher attachment point can.

Hitch positions:

• Seat-post: Temporary or permanent clamp assembly attaching trailer hitch to the seat post.
• Rear axle: Special attachment points, integral to the rear quick release skewer or bolted on to solid axles, hold dropouts cut into the trailer hitch.
• Chainstay: Two-piece sandwiching clamp screws tight over left rear triangle, with protruding socket-and-pin receiver.
• Rear cargo or pannier rack: Some improvised hitches attach to the rear cargo rack or pannier frame. Since rear racks are not structural parts of the bicycle they cannot handle much weight or torque loading.