Into the 9s
INTO THE 9s
How quick will a stock 600 really go?
Hey straight-liner, how much would you spend to shave half a second from your E.T.? Would you believe less than $200? And if you order now, we’ll toss in a set of steak knives...
All joking aside, that’s the cost of a front-end tie-down strap, set of aluminum lowering links (www.diamondpowersports.com) for the shock and a one-tooth-smaller-than-stock countershaft sprocket-the only modifications we made to run a 9-second quarter-mile on an otherwise stock 600.
“You wouldn’t take a lowered bike to Willow Springs, right?” pointed out Pro drag racer and CW guest-tester Rickey Gadson. “It’s the same thing at the dragstrip. To ask me to ride these bikes as they come off the showroom floor is like asking me to ride with my hands tied behind my back. It’s really difficult.”
After making six timed runs on each of our middleweights at Los Angeles County Raceway, Gadson selected the two machines that, based on their 130-mph-plus trap speeds, showed the most potential-the Kawasaki ZX-6R and Yamaha YZF-R6. Respective factory technicians Scott Buckley and Mike Ulrich swapped out the stock rear-suspension “dogbones,” pulled the fork tubes up 1.5 inches in the triple-clamps and bottomed out the forks with the purpose-built tie-down straps (which bolt to the brake caliper mounts and loop over the steering head), dropping each bike a full 4 inches. So set up, the Kawasaki sat so near to the ground that its bellypan scraped on the pavement. Lowering the bikes reduced their tendency wheelie, allowing Gadson to reach wide-open throttle sooner; but why make a gearing change?
“These bikes have tall first gears for roadracing, so I’d have to abuse the clutch to keep the rpm up,” Gadson explained. “With better gearing, I can leave the line at lower rpm, get the clutch out completely and modulate wheelies with the throttle.”
Modifications made and bikes back on track,
Gadson took one look at the slammed machines and let loose with a mile-wide smile: “Now that’s what I'm talking about! Hold onto your hats, ladies and gentlemen...”
Hopping onto the Ninja, Gadson hunkered down over the gas tank and exploded off the line, “hanging the wheel” through the first two gears. “If you have to shift out of first gear early, you kill your momentum,” Gadson explained.
“When we lowered the bikes, they stayed on the ground better and I could run first gear all the way to redline.” A stunning 10.16-second, 131.33-mph pass eclipsed his best time on the showroom ZX-636, an already impressive 10.34 at 131.97.
Were we about to witness history’s first 9-second middleweight quarter-mile?
Not from the Kawasaki. Gadson came tantalizingly close, churning out back-to-back 10.03-second/135-mph runs.
Moving to the R6, though, he cracked the 9-second barrier on his second pass, laying down a scorching 9.98 at 134.90! Even the track staff was impressed.
“Very nice,” came the call from an open window in the tower. “He has an NHRA license, right?”
Yes, ma’am. LACR’s insurance requires said license to operate any vehicle that runs under 10 seconds.
Five passes later, finessing the R6’s clutch, Gadson did the unthinkable. Not only did he back up his previous best, he beat it with a 9.93 at 135.05.
“I don’t have any words,” Gadson stammered. “Hands down, this is your winner. Anyone who isn’t on a Yamaha this year is going to have problems.”
Pause for perspective: In 1995, Gadson set an AMA/Prostar 600cc Supersport record of 10.41 seconds at 129 mph on a Kawasaki ZX-6R. That bike was fully prepped for drag racing, lowered, geared for the conditions and powered by a Bob Carpenter-massaged engine with Rob Muzzy carburetors and exhaust. Aside from the simple aforementioned modifications, our 2005 Kawasaki and Yamaha were showroom stock.
“I haven’t ridden a 600 in a year,” Gadson admitted. “I wanted to go 9 seconds because that was the goal that eluded me when I was racing 600s. But no one has ever done what we did here today. This is big news. A 135-mph 600? That’s crazy!”
Cool thing is, most anyone could see similar gains-if not the outright numbers-by making the same changes.
Shame we can’t replicate Gadson as easily...
-Matthew Miles
