The Frame

• The most important piece of the trailer is the frame. Frames need to be sturdy, have dependable wheels and axles, and should be street legal. Prefabricated freight trailers make excellent starting frames for constructing a motorcycle trailer and are available in many different sizes at fairly low costs. A small- to medium-sized freight trailer will cost around $200 and should meet all of the necessary requirements for a fully functional motorcycle trailer. Most freight trailers can be purchased online or locally and can be assembled by you.
  
  

The Compartment

• The second piece to your trailer is the compartment. Although compartments can be built from scratch, most people opt to use a car top carrier. Car top carriers are also readily available and affordable. You will want to know the exact dimensions of your trailer before purchasing your car top carrier in order to ensure you do not purchase a carrier that will not fit on your trailer.
  
  

Construction

• Once you have acquired all your necessary parts, you can begin building the trailer. Assemble it by bolting together the frame, attaching the axle, installing the wheels and installing your trailer's brake lights and turn signals. If the trailer did not come with lights, be sure to secure them and find a way to install them. One way may be to install them in the actual compartment itself, since the fiberglass will be easier to cut than the metal trailer. Next, fasten the compartment to the trailer by drilling four to six holes through the car top carrier and the metal braces of the trailer in strategic locations for placing nuts and bolts. Once the holes are drilled, bolt the carrier to the trailer. Carefully consider the strength and reliability of the bolts you use. Quarter-inch self-locking nylon bolts and nuts should do the trick.
  
  

Test Runs

• Once the trailer is done, secure it to your motorcycle by the hitch and safety chains and take it for some slower speed test runs before hitting the highway. Be sure that the signal lights are working properly, that the trailer is safely constructed and that all nuts and bolts are tight. You may also make some test runs to determine an optimal weight range.