Uni-go One Wheel Motorcycle trailer

My wife and I have probably traveled close to 200,000 miles together by motorcycle in the 22 years that we’ve known each other. And of all the long trips we’ve taken together, I can’t remember even one on which we’d not been able to stuff into or tie onto the bike the things we really needed with us on the trip. For that reason, and for others relating to safety concerns (real or imagined), I’ve always said I’d never attach a trailer to the rear of any bike I owned. Once again, saying “never” has come back to bite me.

I received a call early last year from Jack Bayer, owner of All Cycle Sales in Tempe, Arizona. It seems that Jack had been in touch with a fellow who owns a small motorcycle trailer manufacturing company named Uni-go that’s based in Christchurch, New Zealand. Jack thought I’d like to look at one of their products. But since I wasn’t keen on the whole idea of trailering, I declined—until he told me that the trailer had only one wheel. This I had to see.
Early in 1997, a young motorcyclist and welder named Chris Van Eekelen was living in Christchurch, New Zealand. He was on his honeymoon when his new bride noticed a small trailer mounted behind a bicycle. She mentioned that she thought it might well adapt to a motorcycle, and with that was born the idea for the Uni-go one-wheeled motorcycle trailer.

Over the next two years, Van Eekelen refined his initial design through trial and error, finally establishing a wheelbase, pivot design, center of gravity and trail length that appeared to give stable and predictable handling on a wide variety of motorcycles. His unique counter-acting swing-arm design incorporates centrally located pivots with the spring located at the front. There is no suspension damping other than the ten-inch motor scooter tire mounted on a three-spoke cast aluminum wheel. The trailer attaches to the bike with an automotive universal joint that permits movement vertically and laterally, and the entire mount is completely rigid in all other respects when correctly adjusted.

Who Needs It?
That’s a fair question. The Uni-go has a load capacity of only five cubic feet and 110 pounds. Conventional two-wheeled motorcycle trailers have capacities ranging from 14 cubic feet and 250 pounds to 30 cubic feet and 750 pounds. Also, the shape and lid size of the Uni-go limit the user’s ability to stow items that might otherwise fit inside. Many Wingers use their trailers to carry airline style garment bags, golf clubs, large tents, and other traditional camping gear. Sorry, this trailer was never designed to carry those types of gear in its interior, though I suppose it could be adapted through the use of bungee hooks, luggage racks, or other such devices.

Weighing in empty at only 70 pounds, the Uni-go was designed primarily for the purpose of carrying the same type of items normally carried in the bike’s integral luggage (if it has any), but a lot more of it. An additional goal was that of disturbing the machine’s balance, handling, and maneuvering capability to the minimum extent possible. At a maximum loaded weight of 180 pounds, this trailer weighs less when fully loaded than many other designs weigh empty. So to answer the question of who might benefit from owning this trailer, we’d answer that the two-up long distance touring couple would benefit. Especially, if like many couples, you consider Motel 6 to be “roughing it.” The Uni-go will permit packing several extra days worth of clothing, extra jackets, boots, etc. It may even be possible to load all gear in the trailer and avoid the added axle weight resulting from full trunk and saddlebags. At day’s end, if the motel manager isn’t watching, the Uni-go could be rolled right into the motel room.

Design Particulars
Is this a new design concept? Hardly. Though designed to be attached to the company’s SR59 Berlin motorscooter, an East German company named IWL sold a very similar design under the Campi brand name sometime around 1960. Aside from the fact that the tongue of the defunct Campi was mounted high on the rear of the towing vehicle, the outward appearances of the Campi and the Uni-go are remarkably similar. In fact, they both utilize a tongue coupling that fixes the vertical centerline of the trailer rigidly to that of the bike, while allowing movement only in the horizontal and vertical planes.

The suspension is a modification of what’s found at the rear of most motorcycles. A double-sided swingarm pivots at its center rather than at its most forward end, and the single spring is located forward of the pivots. The single ten-inch wheel is retained between the rear of the swing-arm legs in typical motorcycle fashion. That is, tightening the axle nut causes the swing-arm ends, bearing inner races, and central spacer to be pinched tightly together to form a solid, non-rotating piece.

The hand laid fiberglass body is mounted on a welded steel frame, and the tow bar is bolted to the front plate. The front plate has several sets of holes drilled in it to accommodate various hitch heights. But as ordered for a particular bike, the trailer will arrive with the tow bar properly positioned so that it’s level when installed.

Uncrating and assembly is straightforward. Attach the wheel and drawbar to the frame, then lower the body onto the frame and install the supplied six bolts. Several options are available including a front-mounted handle that we highly recommend. Without this handle, a loaded Uni-go disconnected from the bike maneuvers by hand like a wheelbarrow with one handle missing.

Loading And Attaching The Uni-go
To test the Uni-go trailer, we decided to give it a good workout on a variety of roads and for a considerable distance. A 2,500-mile round trip from Phoenix, Arizona, to Portland, Oregon, via secondary roads seemed just the ticket!

The first order of business was to load the trailer and weigh the tongue. The manufacturer claims that about 30 percent of the total trailer weight will appear at the tongue regardless of total trailer weight, and that’s exactly what we found. This is in stark contrast to the method for loading a two-wheeled trailer. With a two-wheeled rig, conventional wisdom is to arrange the trailer’s load to obtain a tongue weight between 10 and 15 percent of the total trailer weight. Insufficient tongue weight has caused many a towing rider to experience untoward trailer handling and has no doubt been responsible for more than a few accidents.

With the Uni-go, it’s still necessary to weigh the tongue to be sure you’re not exceeding the bike’s load capacity, tire load rating, etc. But it’s unlikely you’ll ever experience insufficient tongue weight. With a full-capacity load (110 pounds), the Uni-go should have a tongue weight somewhere near 60 pounds, but given the nature of the items you’ll likely carry, you’re unlikely to ever approach that figure. We loaded the trailer to the hilt with clothing, boots, a small coffee machine, and a small cooler for water, and we never exceeded 60 pounds in the interior. Our tongue weight for the trailer and load combo (130 pounds) was 40 pounds.

Finally, we slid the tongue assembly into the special receiver on the bike, inserted the pin and safety clip, and connected the electric plug and safety chain. The receiver incorporates a thumb wheel screw to eliminate side play, but we found that it was difficult to apply sufficient pressure by hand using this wheel. The receiver was found to have side play at each fuel stop. To end this condition, we removed the thumb wheel and replaced it with a bolt and jam nut. Once adjusted with a wrench, it never again loosened.

On The Road
Since the vertical centerlines of the bike and trailer are rigidly fixed to each other, raising the bike from a parked position on the centerstand necessitates raising not only the weight of the bike, but also that of the trailer and its contents. The feel is similar to what one feels with a two-wheeled trailer, but perhaps a bit more pronounced. During slow maneuvering, the bike takes on a slightly top heavy feel, because the trailer and its contents lean with the bike. Although this takes a short while to get used to, there’s no such feeling at speeds above 10 miles per hour or so. As an aside, Uni-go equipped bikes fared extremely well at this year’s Wing Ding trailering competition due to the fact that the trailer leans through turns at the same angle as the bike.

Water placed in a beaker and mounted on the trailer stayed put in turns rather than sloshing out. Is this meaningful to the average user? Maybe not, unless one contemplates the trailer’s ability to hold its footing while turning on wet surfaces. The lean angle should act on the trailer as it does on the bike, shifting the center of gravity and offsetting centrifugal force somewhat.

The first half of the trip was spent getting familiar with the trailer in a safe and sane fashion. Speeds were kept at or below 65 miles per hour, and turns were planned to avoid the need for sharp maneuvering or heavy braking. Speaking of braking, we were pleased at how little our stopping distances were affected by this 130-pound trailer and load combo. Yes, a large, heavy trailer may provide all the comforts of home without undue tongue weight, but 500 pounds or more pushing from the rear in a panic stop situation has caused more than one ruined vacation. This is not to imply that two-wheeled trailers are inherently less safe. Each design has plusses and minuses requiring the application of planning and common sense.

We’ve all heard riders describe their trailers by saying, “you can’t even tell it’s back there.” The same phrase applies to the Uni-go in spades! Because the trailer isn’t as wide as the Gold Wing, and because it follows directly behind the towing vehicle in the same single track, the rider neither feels it nor sees it, not even in a steep turn. Due to the construction of the receiver, it’s not possible for the trailer to separate from the motorcycle unless one forgets to insert the safety pin. The rider eventually learns to relax and not constantly look for the trailer in the mirrors.

The second half of our trip was conducted through some of the most rugged and beautiful parts of California, the Trinity River canyon. As my wife and I rode with our two travelling companions Tom & Brenda Baumen behind us on a Yamaha Venture, Tom used the CB radio to keep me advised of the Uni-go’s behavior. We gradually increased our speeds and lean angles until the foot-peg nubs started touching the asphalt. The trailer leaned with the bike and tracked through the turns effortlessly. As reported by our friend Tom, the trailer would occasionally scoot an inch or so sideways after hitting a bad bump, but it immediately steered itself back behind the bike with no overshoot. Hard cornering, hard braking, hard braking in corners—none of this caused the trailer to deviate from the track of the motorcycle’s wheels or to misbehave in any way.

When towing some trailers, evenly spaced expansion joints in the road transmit jolts to the towing vehicle’s chassis, but we noted none of that while towing the Uni-go. As an aside, we noted no meaningful reduction in fuel mileage from what we normally experience with this particular 1999 Honda GL1500SE motorcycle. Average fuel mileage for the entire trip was just over 40 miles per gallon, even though we weren’t exactly letting any grass grow under our tires!

Construction Quality, Fit, and Finish
Although the Uni-go exhibited exceptional fit and finish from the first time we saw the product over a year ago, we had some initial “issues” with the GL1500 hitch and some features of the axle design. Those issues have now been resolved, and we have no reservations in recommending the Uni-go trailer as a safe, dependable, and good-handling product for fitment on either the GL1500 or GL1800. The trailer itself is suitable for use with a wide variety of other motorcycles. But since we’ve not had the opportunity to examine Uni-go’s hitches for bikes other than the two mentioned, we’ll confine our recommendation to those two, at least for the time being.
Uni-go has recently come out with an expanded accessory line including soft luggage. These bags are nicely made of extremely heavy material, and they keep the trailer’s contents segregated as well as help the owner make best use of the interior space. Other options include the handle mentioned above, a vinyl bra, a chromed drawbar, and various wheel styles.

Because the company is based in New Zealand, we suggest browsing their website
www.uni-go.com for a complete list of options, prices, and U. S. distributors.

Questions can be e-mailed to Chris@uni-go.com


—Stu Oltman
Wingworld