Duke's Den: The WFO Nut

I’ve been testing factory-supplied motorcycles for more than 20 years, and I’m proud to say only a few of the 700-odd press bikes I’ve sampled have ever been placed improperly on the ground, i.e. crashed.

Testing motorcycles can be a dangerous occupation, and the stakes are raised exponentially when testing the fastest sportbikes on earth. The best venue for testing superbikes with liter-plus-sized engines is, of course, a racetrack. However, the aforementioned superbikes have lights and license plates, revealing their street intentions, so testing on public roads is a necessary part of the process.

And then there’s the devil on a shoulder, desperately pleading to feel shrieking literbike power with levels of acceleration as strong as anything else on street-legal wheels. Hold that throttle on a little longer; float that tire a little higher…

The devil was strong in 2006 when comparing the latest crop of Japanese superbikes for another publication. The 2005 Kawasaki ZX-10R was an epic literbike, a no-nonsense, stripped-down brawler with the best power-to-weight ratio I’d ever sampled from a production motorcycle. Then Kawi lost the plot in ’06 and delivered a porky-looking machine that violated the cardinal rule of building sportbikes: Must always get lighter.

So, I’m riding up S-22 in the early morning after spending the night in a local hotel, and the ZX is challenging me to twist its grip a little harder. I scythed into a corner, feeling the tires gripping the asphalt. The road opened up to a tempting straight stretch, so I gave a greedy twist and fiercely rocketed ahead. It only took a second to go from street speed to track velocities, and the canyon wall behind the next corner loomed large, so I rolled off the throttle and began to reach for the brake lever.

Except the throttles remained stuck open!

Given a second to think about the situation, it would be easy to come up with a remedy to the predicament – pull the clutch or hit the kill switch. But I didn’t have a second to think about it, as I was on one of the quickest-accelerating vehicles on the planet hurtling toward immovable rock wall. So, instead of calmly reaching for the clutch lever, I grabbed the brake lever in an effort to slow my inevitable implosion into the cliffside.

Know-it-alls on motorcycle forums often brag about how they believe they can outbrake an antilock brake system. That might be true in a controlled-test situation with expert riders, (though I’m skeptical), but time compresses when faced with imminent death, forcing a brain to react to emergencies rather than think about brake modulation.

When pulling the brake lever did nothing to slow me, I pulled harder. That’s when the front tire began to skid while the engine kept cranking out its power.

I slightly eased off the brakes, which caused the front tire to regain its proper spinning motion, but that new force induced headshake into the chassis. Great, I’ve prevented a lowside by causing a highside.

Then, as if by the stroke of a god’s magic wand, the ZX’s throttle shut and caused the headshaking to vanish. Hey, look, there’s a corner coming up and I just might be able to slow enough to go through it! The Kawi stayed upright, and I swallowed hard to urge my heart back out of my mouth.

No one’s ever more alive than after they nearly die, so, congrats to me! But WTF caused this near-catastrophe?

We experimented with the throttle to see if we could replicate the problem, warily covering the clutch lever in case the throttles again stuck open. Dozens of tugs of the throttle would operate flawlessly. Then it wouldn’t, sticking open at random times and at random throttle openings. It’s the kind of thing I might want to blame on a ride-by-wire throttle, except R-b-W was still several years away from a ZX.

So the demonically possessed 10R went back to Kawasaki for investigation. The problem was difficult to diagnose, even by the experts at Kawasaki. It would be beyond embarrassing if no issue was found, leaving me to tell my sketchy story about how a motorcycle mysterious tried to kill me. Then, finally, the anomaly was discovered.