Airbag System Component - Well Made In The UsA - MC Garage

Tips, Tweaks, Fixes And Facts

Why does the inflated airbag on Honda's new Gold Wing look like a big, pink butt? That is the single most prominent question motorcyclists have about the first production bike so equipped. And we're delighted to be able to provide you with the answer: The, er, rounded shape, which evolved over the 15-year testing and development program Honda underwent to create the airbag system, is designed to keep the rider in place should a collision cause the bag to inflate. And the color? It's the same as Honda's car airbags-pink. At least that's what Bob Axe, vice president and plant manager of the Honda of America Manufacturing's Marysville Motorcycle Plant (MMP), told us while nearly choking from laughter at the question.

Such scatological humor shouldn't diminish the sizeable task faced by MMP, both in building the airbag-equipped Gold Wing and in ensuring the system's reliability. After all, it wouldn't do to have airbags failing to open when they should, or inflating spontaneously like possessed pans of Jiffy Pop.

Point man for the MMP's efforts is Tom Briggs, staff engineer at the plant's new model center; he also got the MMP up to speed when it was preparing to build the 2001 GL1800. "Honda actually benchmarked NASA on how to guarantee the airbag wouldn't deploy unexpectedly, and how it would deploy correctly," Briggs said. "There's a NASA study on how to achieve six-digit-nine reliability." That's where the probability of failure doesn't exceed one in a million, or 99.9999 percent reliability. The MMP also relied heavily on the airbag experience of Honda's automotive division.

Briggs said those resources translated into some brand-new procedures for the Marysville plant, such as super-strict handling guidelines: If a plant associate drops any airbag-system component-the airbag module (airbag and inflator), airbag itself, the system's ECU or the G sensors that attach to the Gold Wing's fork legs and tell the ECU when to deploy the airbag-that component is scrapped, no questions asked. What's more, all the key components come from existing suppliers in Japan, because, as Briggs said, "Every time you change something, you introduce the possibility of problems." Potential failures, in other words.

Even more important, though, are the new levels of traceability of parts and of the production process, to a degree unknown before at the MMP. "Traceability," Briggs said, "goes hand in hand with reliability." For instance, the MMP uses a bar-code reader to scan labels on all key airbag-system components and automatically ties each one to the VIN of a specific motorcycle. This procedure was already in use at Honda auto plants. "It's essentially lot control," Briggs says. "We'll know what lot of components a failed part came from. And the number of components per lot is very small."

For traceability in the production process, Briggs said, associates use a special tool called a DC (direct current) nut runner, basically an electric torque wrench widely employed in production and assembly facilities, including the MMP's engine assembly area. The tool is used to torque the fasteners for the G sensors, airbag stays and airbag tether stays. What's more, the tool stores the information those items have been torqued correctly with the bike's VIN number. When it reaches its torque value, it emits an audible signal that sounds like a ricochet from a cheap sci-fi movie: Pwee-yoo!

It's easy to forget the airbag system might have an effect on some other part of the motorcycle and the production process. Returning to the notion that change can introduce problems, any additional electrical component adds wiring to what is already a fiendishly large and complex wiring harness, making positioning of the harness crucial. For example, if the wiring harness (which is installed early in the process, about the same time as the engine) is out of position by as little as half an inch, it can cause bodywork fit problems at the end of the production line. Honda spent months trying to figure out just the right length for the harness.

Ultimately, almost everything related to the airbag system-the parts, sourced in small lots from longtime vendors; the tools, such as the DC nut runners; even the associates who performed the assembly-is all traceable to a specific motorcycle's VIN number. It shows just how extensive Honda's and the MMP's efforts are to maintain the system's reliability.

And it's far more important than why the airbag looks like a big, pink butt.