How did Co-Motion decide on standard tandem sizes?

A little insight on how Co-Motion arrived at our system of sizing our standard tandem models…

We started our business as a custom frame builder. As a custom builder offering no stock models at all, it makes sense to show potential customers how they can benefit from a custom frame. That’s an easy sell for people at the large and small end of the scale, who can’t find anything in the bike shop to fit them, but average sized people know they can get get fitted fairly well with an off-the-rack bike from any number of manufacturers. Those that can be enticed to look into a custom frame usually have something different in mind, like a new kind of tubing or unusual geometry.

Any frame builder worth a hoot develops a unique style and design philosophy in time. If they’re paying attention to their customers, they will find a common theme to the bicycles they’re making. Some builders are associated with a material; like Merlin and titanium, while others make a name for themselves with wild paint jobs, like Landshark. More subtle trademarks, such as a specific handling characteristic, or a reputation for excellent quality, are more difficult to identify, but certainly no less important.

When a small-time frame builder decides to delve into stock offerings, it is very important that some characteristic sets his product apart from mass-produced frames. For the product to sell reasonably well enough for the builder to stay in business, it can’t be so weird that it needs a 400-page manual to explain its purpose. Mass marketing is usually out of the question. Demand will develop if there is a need or desire for whatever quality is offered. A lot of little guys fail when they attempt to make this transition, because they can’t describe what’s unique about their product, or haven’t fully thought out what they have to offer other than custom sizing. It’s a difficult transition to make when you consider the justifiably suspicious nature of many consumers. Everyone wants their money’s worth.

Bicycle fit is often approached as a science, but it’s really too subjective to apply any single formula to every body. Fitting formulas are useful as guidelines, but should never be applied too rigidly. What works for a 19-year old wunderkid doesn’t apply to a 50-year-old with a history of back problems or injuries. And, the purpose of the bike plays a key role; you don’t want to be in a time-trail position on a touring bike, for example. Still, good fitting advice can work wonders to improve performance and comfort for any cyclist. Whether good fit is achieved using components vs. frame size is less relevant to comfort than performance. You may be able to get the body in a good position on an ill-fitting frame, but good performance isn’t simply a result of good positioning.

For a rider to feel completely at ease with a bicycle, they need to feel confident in all potential situations. Fast descents should feel as natural as a flatland sprint or an out-of-the-saddle climb. Are racers the only ones that need good fit? Nope. As you spend more time with your bike, fit becomes more important. Fit-related frame problems become apparent. If you’ve ever felt like you were going to fly over the handlebars when descending, or had trouble keeping your front wheel on the ground while climbing, you know what I mean. Those are extreme examples symptomatic of bicycles extended beyond the size range they can effectively support.

Putting a super-extended stem or extended-setback seat-post throws off the balance of the bike, and it’s easy to get yourself in a situation where you create numerous new problems, attempting to solve just one. A common mistake is sliding the saddle back to extend reach, without consideration for ideal positioning of the knee over the pedal spindle. We also see a lot of tall guys who fear going downhill on their bike because too much of their weight is suspended above the front axle. These balance problems are far more sensitive on a single bike than a tandem.

Tandems benefit enormously from their long wheelbase and heavy load. Changing stem extensions and angles therefore has far less affect on handling character than on a single bike. The importance of good positioning is still relevant, but the tandem has an advantage over singles due to its steady disposition. Being fully capable of producing both stock and custom tandems, we do our best to help our customers decide what the best choice is. If we can fit you nicely onto a stock frame, that’s what we’ll recommend. Although we charge more for custom frames, there’s no financial motivation for us to sell one vs. a stock frame. The pricing for each is based on actual labor and design time.

We don’t produce 64 stock tandem sizes because we’ve found that we can fit close to 90% of our customers with just a few sizes. Some people certainly choose a stock bike instead of a custom unit for economic reasons, but they’re also benefiting from the fact that we don’t make 64 sizes, which would throw production into chaos and raise our cost per unit significantly. For the necessary custom bikes, we do our best to work with every popular fitting system and we offer our own fitting guide that can be completed at your Co-Motion dealer or at your home. Whether you need a custom frame, or one of our stock sized bicycles will work for you, we consider listening our best tool. We know that we need to hear what’s needed to keep our customers satisfied.