A home-made trailer can be a satisfying project, but there are numerous technical difficulties to overcome (aside from manufacturing with limited resources). A single side swing-arm mount throws an extra spanner in the works.

Some of the challenges are:

1) Weight (overall and distribution)
2) Correct alignment with motorcycle axis
3) Stiffness

The other main lessons are:

1) Mock things up and try them before carving the design in stone (e.g. test drive with bag of cement in the back - how does it respond?).
2) Remain flexible/self-critical at all stages of the project.
3) Simplify whenever possible, and if in doubt go for strength.
4) Accept that you will probably not get it right first (or second) time. Developing the design is the most gratifying part of it.

Good luck - Guy

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This article by Stephen R James can be found in Vehicle System Dynamics Vol 43, No8, August 2005, 581-599

PhD Student Stephen James

This article compares (both in the field and by computer modelling) a number of one wheel trailer designs and concludes (I paraphrase) that the most stable trailer/hitch sytems where those that held the pitch and yaw axis of the hitch forward of the rear wheel and roughly the same height as the trailer loadbed. Using this method loads of up to 200kgs could be safely transported around speeds of 20m/s. The more the axis were moved rearward (as in the Trailtail design) the less weight that could be carriied with any level of stability. With a hitch axis to the rear of the rear wheel safe loading was reduced to some 40kgs. This may however may be adequate for most users.

Obviously there is so much more to the study and I have just attempted to give a flavour. I would recommend anyone seriously concerned with the safety of a monowheel trailer design to get a copy, after all even paid for it could save a serious amount of time devoted to trial and error in producing a viable unit


I hope to be producing a monowheel to carry camping gear with my Highland. The problems with standard load carrying systems for me are as follows:-

1. The Highland has an extreme seat height making getting on and off difficult and even more so when carrying a top box, tent and other articles in the pillion position.

2. When fully loaded I find it impossible to pick the bike up after a spill without assistance or removing some of the load (the pannier on the down side does help to keep the bike from laying flat however).

3. The luggage weight carried high up changes the riding characteristics and means I have to really concentrate far harder in the rough removing a lot of my riding pleasure. Watching the Trailtail river crossing video I have been convinced a single wheel trailer will substantially reduce the instability on rough ground making the bikes riding behaviour nearer to it's unloaded state.


A trailer that can carry up to 40kgs will be fine for me. I hope to fabricate a unit using steel tubing similar to that used in crash bars for motorcycles. The axis and suspension using rubber boot covered rose joints, a 20inch 48 spoke hd bmx rim with one of the heavier Maxxis tyre types and finally a suspension unit from a mountain bike. I know many members will hold up their hands in horror thinking that these component parts would not be strong enough. What I want to avoid is a heavyweight trailer that is a serious drag before the luggage is attached. Experience of these parts in seriously overloaded situations makes me think this is a good place to start. Comments welcome.

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"The trouble with the world is that the stupid are cocksure and the intelligent are full of doubt." -Bertrand Russell

Well we've put about 2k miles on the RIG now, and it's been good fun. Obviously most of them have been road orientated, but there have been a couple of dirty moments.

On the road you (I) hardly notice that it's there, especially on a good surface at speed. Slow speed manoeuvres you can feel it, but not half as cumbersome as I was expecting.
Mileage is still excellent, it doesn't really seem to have affected (effected?) that at all.

We're now in San Felipe, Baja. With the torrential rains a couple weeks back, there were huge chunks of road missing on the route from Ensenada, which forced detours through sometimes deep dirt.
This wasn't such good fun on the big heavy old BMW with trailer in tow. It's do-able, but I realise that I very much enjoy off road, and this arrangement is simply not suited to the rough dirt at all.
I'll avoid the off road now, until I'm back on the Honda.

Thanks for the encouragement everyone, I really appreciate the positiveness of the response. A big part of this experiment is simply to try something interesting, something that most people don't bother with.

A couple of photos..

Quite a high centre of gravity, which might account for the bad performance on dirt roads.

At a bikers' meeting in Darwin I met a couple on a V-Strom 1000 with a self-constructed trailer based on a 44 gallon drum with a single wheel. The connection to the bike was similar to he bicycle trailer "Bob Yak". Centre o gravity was very low, allowing him to travel all dirt roads in OZ. Unfortunately no pics

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Only when we pause to wonder
do we go beyond the limits of our little lives.
(Rod McKuen)