True Suspension Ultralights

When it comes to ultralight manual wheelchair performance, rigidity has forever been the ultimate standard. After all, a rigid frame best translates the user’s push strokes and movements into the wheelchair’s momentum — an extension of one’s body in motion.

However, rigidity comes at a personal price. Despite advanced frame materials and designs, as well as wheels and casters that absorb shock, rigid ultralights can still prove bone-jarring under rough, bumpy conditions, a factor that can increase user fatigue at best, and cause pain at worst. Over the past two decades, a host of “suspension” ultralights have come and gone, able to soften the ride, but only while adding tremendous weight and bulk that frustrated users.

If only there were rigid designs that could integrate a true, shock-absorber suspension into a slim, ultralight package. Fortunately, two “boutique” builders are showing off the latest wave of true suspension manual wheelchairs — and they’re ultralight and ultra-cool.

Reinventing the Rigid
When Jeff Adams and Christian Bagg — both users and engineers of high-performance wheelchairs — set out to create ultimate suspension wheelchairs for everyday use, they couldn’t help but simultaneously reinvent the manual wheelchair. The result is the Icon, a true suspension ultralight that’s so far beyond conventional rigid wheelchairs that it comes full circle into arguably the most functionally-practical rigid ever built.

At the center of the Icon — literally — is a vertical shock upon which the seat sits, creating a “seat-post” design. From that center shock-absorber seat post, the rear wheels and front end offshoot, essentially floating the user atop a shock for true suspension. Adams and Bagg note that because the user is atop a vertical shock, dampening is optimized and there’s no effect on the actual wheel or frame alignment during pushing.

However, beyond the center shock, which is adjustable for different user weights and can be locked-out for a rigid ride, the Icon’s frame design — weighing in at 22 pounds as a complete wheelchair — is truly revolutionary. With clamps and a few set-screws, virtually every dimension on the frame can be changed in minutes, and sometimes seconds. A simple turnbuckle adjusts the backrest angle on the fly. The frame length is adjusted via two quick-release clamps, allowing the whole front frame to telescope outward or inward. The seat height is adjustable by threading the center seat post up or down. And rear-wheel offset and camber is adjusted via four Allen-head bolts. The adjustment list goes on and on, but to see the chair being totally readjusted in under 10 minutes is mind blowing. For those right out of rehab or with changing needs, the ability to easily and radically reconfigure the entire frame makes for arguably the most adaptable high-performance ultralight ever designed.

With the Icon using complex manufacturing methods (the “seat post,” for example, is based on very high-end fabrication processes), the cost is also high-end, starting at $4,295. However, when one considers that the Icon can be reconfigured as needed over the years, as well as its exceptional performance characteristics, it may be among the few mobility products that can serve users for a decade or more.

For those who want a traditional ultralight manual wheelchair design, but with true suspension, Per4max Medical offers the Shockwave. Starting off with a fairly conventional over-the-hub frame design, the Shockwave features a minimalistic rear swing-arm that allows the rear wheels to compress upward (or the seat downward), offering several inches of travel. A Fox air-adjustable mountain-bike shock absorber provides the suspension, soaking up rear-wheel lumps and bumps.

What allows the Shockwave to excel where others have failed are its minimalistic modifications to allow high-end suspension. Rather than adding bulky, heavy sub-frames, the Shockwave merely adds a pivot point on the frame in front of the rear camber tube, then runs a single shock between the camber tube area and seat frame. The result is true suspension while adding hardly any weight or bulk — it still looks like a slim-line ultralight, weighing in at around 20 pounds. What’s more, the Shockwave carries a full array of rehab options, so it can be configured for higher-level injuries who likewise need a suspension ultralight. At $3,295, the Shockwave is competitively priced near the high-end arena of custom-built ultralights.

When to Go All-In
Indeed, there are many components that go into an ultralight manual wheelchair’s shock-absorbing characteristics — from frame design to frame material to caster composition, and on and on. However, while many component choices can reduce jarring the user, none are as effective as full-out suspension, where the user sits atop a literal shock-absorber. Sure, suspension ultralights cost a bit more; however, if you’re one who traverses the rough stuff or routinely encounters wheelie-popping curb drops, a suspension ultralight may go a long way as a sound investment in comforting your back.

Resources
• Icon Wheelchairs, 888/461-5759, www.iconwheelchairs.com.
• Perf4max Medical, 866/648-6891, www.per4max.com.

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