Trike for Four – Part 1

It is often said that tandem bicycles will either make or break a relationship. They place two riders in close proximity for long periods of time for an activity in which the contributions and goals of both riders must align in order to keep moving forward.

The captain, the person that sets direction, relies upon the stoker, the person who acts as the engine, to provide propulsion. Should either the captain or the stoker find annoyance with the other rider, the outing will almost certainly end in misery. Conversely, a pair in harmony will have a ride to remember (though it can be said that miserable rides are also quite memorable).

What do two people do when a ride devolves into misery? They ride separate bikes. They get their distance. They ride four lengths apart from each other.

But what if they didn’t have that choice? What if one of the riders was absolutely dependent on the other for all riding, tandem or not? That is the case for a rider we’ll call “Tim”.

Tim was a college graduate before deciding to enlist in the military following graduation. His enlistment eventually led to his deployment as part of the latter Iraq war. During a confrontation, shrapnel from incoming mortar fire ripped through Tim’s eye severing his optic nerve and causing significant brain trauma. As a result, Tim is now completely blind.

And Tim wants to ride a bike.

As he has no other physical limitations, it is entirely possible for Tim to ride an upright tandem bicycle. In fact, he has done so on a number of occasions having clocked a 35 mile ride at one point. There is, unfortunately, an inherent danger in doing so. Due to the delicate nature of the cranial reconstruction he received following the shrapnel damage, Tim is unlikely to fully recover should he fall from the height of an upright bike and sustain a head injury.

After a good deal of research, Tim and his family determined that a recumbent tandem trike would be the best overall fit to get him back to pedaling. It allows Tim to contribute power while the captain guides the ride. It is also built very low to the ground and on a much more stable three wheels to sharply reduce the possibility of dangerous falls.

With a rider as capable as Tim, this would perhaps mark the end of the story, but there is a unique facet here: multiple captains. Tim will always be the stoker due to his visual impairment. There are no issues with that since the seat and stoker crank will never require adjustment. Tim is the only person who will stoke his trike. However, there are no fewer than three potential captains: Tim’s father, mother, and girlfriend.

For those not familiar with typical recumbent configurations, recumbents are tuned to their riders. On an upright bike, differing rider leg lengths are accommodated through a simple adjustment of seat height. For proper fit, there is also handle adjustment, but most riders need only to adjust the seat up or down to reach the pedals properly. Recumbent bikes normally feature a fixed seat – it does not move back or forth,up or down. The adjustments for leg length (referred to as external seam or x-seam) all happen through movement of the pedals closer to the rider or farther away. Moving the pedals means changing the chain length, a painful process. This is why people trying out a recumbent for the first time often feel that the bike doesn’t fit them well – it doesn’t.

Three captains means three different x-seams. The trike needs to be able to quickly adjust for each captain and not require the dirty process of removing or inserting quicklinks to change chain length. Fortunately, Tim and his family decided on a Greenspeed tandem trike. Greenspeed is known both for their build quality and their customer service. When asked how multiple captains could be accommodated, the answer from Greenspeed was quick: chain tensioner. Greenspeed suggested installing a chain tensioner much like the one they sell with their Anura delta trike. This device automatically releases slack and takes it up when the front boom is adjusted, allowing for a flexible range of x-seams.

Had Greenspeed not offered this solution, Tim would be limited to a single captain and would have his riding limited by the availability of that lone sighted partner. Once constructed, Tim’s trike will be open to nearly anyone who wants to take the front grips.

The measurements are taken. The colors are chosen. The options are selected. Now the wait begins for Tim and his many captains as his trike is being built.