Adding A Third Wheel:
The second part in a series on sidecar attachment

by Sev Pearman

In our first article we touched on the basics of attaching a sidecar to an existing solo motorcycle. In this installment (sorry) we select and purchase a bike for our yet-unnamed project.

We wanted this project to appeal to as many of our readers as possible. It does no good to talk about mounting a Titanium-bodied sidecar onto a Britten or other exotic. Who has the dough for that? With a hopeful budget of $6,500 we would seek out and buy a reliable bike and pair it with a new sidecar. Note that this amount has to cover any hidden surprises that can come with buying a used bike, the cost of the sidecar, installation and/or mount modifications, as well as future sidecar rig “enhancements.”

After doing our homework, we budgeted no more than $3,000 for the bike. Of that figure, we retained $500 for taxes, title and bike repair contingencies. This gives us $2,500 to spend. $2,500? OK, that kills any Harley, other recent big cruisers and most Euro bikes. So, what kind of bike can we get?

A large percentage of registered motorcycles consists of both cruisers and inline 4-cylinder Japanese motorcycles or the Universal Japanese Motorcycle (UJM) Other options considered were late-model BMWs or Moto Guzzis. Sportbikes and other fully-faired motorcycles weren’t considered for this project due to the extra headache, labor and cost in cutting the bodywork to receive the sidecar mounts.

It is desirable for the donor bike (also called tug or mule) to have a traditional tube cradle frame. The exposed frame tubes easily accept the four mounting clamps from most sidecars. In addition, it is easiest to work with these type of frames should there be any obstruction or clearance issues. For these reasons we ditched any naked bike with a beam or perimeter frame.

While several cruisers fit the bill in our meager price range, they were collectively nuked with a ‘delete’ keystroke. I would have to build and ride this contraption and while I have ridden many cruisers that I have enjoyed, they aren’t my cup of tea. Hey, I’m spending my money.

I have a love for most twin cylinder bikes and have over 80,000 miles on airhead BMWs. It seems natural to pair a dorky BMW with an equally dorky sidecar, but hold the phone. It is possible to find a solid /6 or /7 model in our price range, but we flushed this option for two reasons. First, while late-model airheads have tube frames, they require additional bracing to handle the stresses generated by a sidecar. This can be done but it requires additional money. Second, our pitiful kitty would permit only the purchase of an older, less-powerful BMW.

Similar realities dashed any hope for a Moto Guzzi. This is unfortunate as Guzzis make excellent tugs. The Tonti-frame models readily receive sidecar mounts. Guzzis are strong, make that cool V-twin sound, have perfect 90º primary balance, and like airhead BMWs, are shaft drive. We wanted one of the liter displacement models but our meager $2,500 permitted only a tired high-mileage nail from the mid-to-late 80s or a less-desirable smaller-displacement model.

After all of our fun and games aboard the delightful CB750-powered “Metallic Waste” (MMM #71) we wanted a rig that would be comfortable cruising at 75 mph. We decided to put ample horsepower and torque ahead of Euro–panache and prestige.

This left tube-frame inline 4-cylinder UJMs. While not as flashy as a cruiser or as cool as a European bike, they do have their advantages. Each of the Japanese Big Four manufactured tens of thousands of them. This makes them plentiful and cheap. They are as a group strong and reliable with excellent parts availability. You can usually find an online group that caters to your specific model, even if it is the half-model year only lime green Kust-o-rocket with the factory Hibachi®. These groups are an excellent resource for parts and advice.

Further research steered us toward the Suzuki 1200 Bandit. These have a traditional tube frame and are powered by a GSX-R 1100 motor retuned for midrange torque. More torque is good. You cannot have too much torque when you have a sidecar. Bandits are plentiful, proven strong and have excellent aftermarket support.

Other hack riders have come to the same conclusion and selected a Bandit for their mule. Sidecar shops have done many installations on Bandits and frame mounting hardware is available. The only kink in the armor is that the Bandit has a chain final drive. I hate chain maintenance. I’ll admit that I have a pathological loathing of this task. I resent the effort, the cleaning, the adjustment and inevitable replacement of both chain and sprockets, especially when there is a clean elegant proven solution in a shaft final drive.

The downside of shaft final drive is that you cannot alter gear ratios as you can with a set of sprockets. If your bike makes less than 75 horsepower and you plan to burn the interstate, this could prove problematic. With a smaller displacement mule you simply gear down. This restores acceleration. You can still cruise on the freeway with the tradeoff being higher engine speed and proportionate lower fuel economy.

BMW and Moto Guzzi actually offer final drive units with different ratios. It is possible to cleanly gear these bikes up or down. This was another reason we liked these two makes for our mule. With only a couple of exceptions, you can’t change the final drive ratio on a UJM.

There are many UJM models with shaft final drive in our price range but I hesitated. Clean, solid low-mile examples of Honda CB900 Customs, early unfaired Goldwings, two-valve Suzuki GS-1000Gs, shaftie Kawasaki KZ1000 and Yamaha XS-1100s were available but none of these were manufactured past the early 80s and we wanted something newer. While you can get parts for all of these models, it is generally easier to service a newer bike. Plus, this rig will deliver bundled issues of MMM and a newer tug will extend the service life of our outfit.

I was stuck on this stalemate until I literally stumbled on the answer – a Suzuki GSX-1100G. Like the Bandit, they are powered by a midrange-tuned GSX-R 1100 motor. Only sold in this country in ‘91 and ‘92, they came and went quietly. While not popular when sold, these have many features that make them excellent tugs: tube frame, 100 horsepower, a long wheelbase and shaft final drive. While hard to find, they fit our basement budget. Best of all, I would be driving a mule built in the 90s.

We paid $2,500 for our 1991 GSX-1100G with good tires and 40K. The mileage didn’t scare me. It was less important than having a newer tug with a shaft. Its garish electric-blue paint quickly earned it the name Beluga. I put a few thousand miles on her last summer to find any faults. There were none. Confident with our choice of tug, I directed my energy to selecting a sidecar.

Next installment: The hack arrives!

M.M.M.

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