Here is how I made a strong and permanent hitch for my bike trailer.

The trailer is a Bellelli Eco Trailer Maxi which I modified (with a little woodworking) to a luggage rack level hitch. Why? The original seat post hitch did not adjust high enough to ride level - and I hate seat post hitches, as they get in the way when mounting/dismounting (men's frame).

http://www.bellelli.com/index.cfm?method=mys.dettprod&classe=14&id=40
http://www.mammacangura-na.com/eco_trailer_maxi.html

Also, the rack-mounted trailer hitch does not obstruct the rack (and space above), leaving it free for panniers and (er) luggage.

When not towing, the eye bolt is a convenient and strong point to tie off luggage straps, bungees etc.

Step 1: Tools and Materials

YOU WILL NEED:

Eye bolt (mine was 6mm diameter)
Nut x 4 (to fit the eye bolt)
Washer x 4 (to fit the eye bolt)
Pair of rail clamps from an old bicycle saddle
Spanner (to fit the nuts)
Hacksaw (maybe)
Some strips of inner tube

Ideally, the eye bolt should be as thick as possible, whilst still fitting through the holes in the saddle clamps.

Step 2: Assemble

1. Screw one nut right up the eye bolt to where the threads end.
2. From there, the order is:

Washer
Clamp half A
Your bike luggage rack
Clamp half B
Washer
Nut

Space

Nut
Washer
Clamp half B
Your bike luggage rack
Clamp half A (for symmetry)
Washer
Nut

Step 3: Install

My luggage rack is fairly round in cross-section, but I still used one strip of inner tube inside the clamps for grip. My old bike had more of a square profile to the luggage rack. So experiment with more or less inner tube.

The hitch clamps on to the back two bars of the luggage rack.

1. Tighten Nut 2 (see photo).
2. Turn Nut 3 to pull away from Nut 2.
You should just feel resistance, then stop - or you will bend the rack!
3. Tighten Nut 4.

If your eye bolt is really long and fouls the third rack bar . . .
you will need to cut it down with a hacksaw or Dremel.
It will look neater cut to length, so the choice is yours.

Now you are free to use this hitch to attach your own bike trailer creations.
But stay tuned if you want to see how I use it . . .

Step 4: Hitch Up!

The hitch on the trailer is a vertical bolt on to which I screwed a piece of air pump hose, to cover all the threads.
I use a large rubber washer (I think from an old washing machine?) between the trailer hitch and the eye bolt.
I lash the two together with a 3 feet long strip of inner tube. It has 6 holes punched at one end, 3.5 inches apart).
I used an office hole punch to make the holes.

Watch the video!

I lash the hitch together with the inner tube strip. On each turn, I pass the hitch bolt into the next available hole in the inner tube, until there are no holes left. Then tie off with the remaining section of rubber.

Step 5: Road Test

The hitch ensures that every part is both separated and lashed tightly together with flexible rubber.

I actually flipped the trailer on its side (loaded with about 4 stone). I hit a speed bump!
The hitch stayed lashed together.
The eye bolt did not turn.
The wood did not split and the hitch bolt did not bend.

The tub was a little scratched - and my pride was dented!

Thank you for your interest and encouragement.
Johan J Shaw's Blog
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