Old name, new tire: Dunlop unveils its latest high-performance street radial

story by Lance Oliver
photos by Kevin Wing

How many times have you heard a race announcer say that a rider "threw on a set of qualifiers and set a new lap record."

Dunlop is counting on a lot of sportbike riders throwing on a set of new Qualifiers — with a capital Q — and setting their own personal bests, whether that's a quick lap at a track day or more confident riding on the street.

In racing lingo, qualifiers are short-lived, sticky tires good for a hot lap during a qualifying session. With that new connotation in mind, Dunlop pulled the old Qualifier trademark out of its archives and put it on its new street performance tire, which replaces the company's current D208 ZR. Dunlop says the D208 ZR remains the best-selling sportbike tire in the United States, despite its age in the marketplace. So a replacement tire is a big deal for the company.

With that in mind, Dunlop rented the Spring Mountain Motorsports Ranch at Pahrump, Nevada, and let the motorcycle press test the new Qualifiers back-to-back with the current D208 ZRs.

The D208 ZRs were good tires. But it only took a few laps to see what a big stride forward Dunlop has made with the Qualifier.

First of all, the changes. On the front, Dunlop made the Qualifier's profile more triangulated than the D208 ZR to make turn-in quicker. The front Qualifier's profile is virtually identical to that of Dunlop's track-day tire, the Sportmax D208 GP. At the rear, the Qualifier's profile is virtually the same as the D208 ZR's.

The D208 ZR's "cosecant wave" tread pattern is replaced by grooves that follow the direction of the force placed on the tire at various lean angles.

Dunlop's Mike Manning said a lot of research and development time went into seeking just the right compound for optimum sport performance. The Qualifier's blend of three polymers provides more grip and also warms up more quickly, Manning said. The Qualifier also is more compliant, and one result is a larger footprint at all lean angles (click here to see chart provided by Dunlop).

Finally, a rear Qualifier is about a pound lighter than a rear D208 ZR, which aids quicker acceleration and steering.

To show off these improvements, Dunlop borrowed some 600cc and 1,000cc sportbikes from the four major Japanese manufacturers to let us try their new tires.

So how do they work?

The difference between the Qualifiers and the D208 ZRs was immediately noticeable. The D208 ZRs were not a bad choice for a track day, but after a few laps, especially when the temperatures were warm, the rear would start to feel greasy. It was never a problem because the sliding was minimal and controlled. But I always knew I was losing a little grip.

With the Qualifiers, I could ride as hard as my skill allowed and the tires never exhibited any greasy feel. They just stuck.

As Dunlop promised, the front did make the bike turn in more quickly and although I'm no Superbike hero when it comes to late-braking maneuvers, other test riders with lots of racing experience on their resumes said the Qualifiers gave them considerably more confidence under hard braking. Credit that to the larger contact patch.

Sensors keep track of rear tire temperature in real time — just one of 18 channels on Dunlop's telemetry-equipped motorcycle.

Just the facts: Telemetry makes testing a bit more science, slightly less art

Tire companies have far more tools at their command today than ever before when it comes to designing a new tire. Dunlop engineers talked a lot about finite element analysis and finite element modeling when describing how they designed the Qualifier. These techniques allow the engineers to use computers to predict how a tire will perform even before it's built.

That means that Dunlop builds about half as many prototypes of a new tire for testing as it used to. Lower R&D costs help keep consumer prices from spiraling.

But eventually, prototypes must go onto the test tracks. That's when test riders such as Danny Roberts and Rich Conicelli provide all-important feedback.

Even the prototype testing has been computerized and made more objective, however. Dunlop uses a Suzuki GSXR1000 fitted with an 18-channel telemetry system to monitor exactly what's happening to the motorcycle and tires while the test riders are lapping.

Telemetry enabled Dunlop engineers to know not just that the Qualifiers were better than the D208 ZRs, but also where and why.

Test riders were pleasantly surprised when they saw that their best lap around Virginia International Raceway was a whopping 3.5 seconds faster than the best lap on the D208 ZRs. But telemetry showed that the big jump in performance was due to increased side grip. The GSXR with the Qualifiers mounted was anywhere from 3.5 mph to 8.3 mph faster through VIR's turns.

Test riders still have to do the riding. But now the riders — and the engineers who build the tires — have more data to help them understand exactly what's happening on the track.

Of course even two days at the track doesn't give any clue about how many street miles the Qualifiers will last or how they'll perform in the rain or in cool conditions. But on the second day of the test, when conditions were cloudy and cooler, the Qualifiers did seem to live up to their promise of warming up more quickly. That could be a real benefit on the street, where D208 ZRs can be slick on cool days.

The benefits for a day at the track are clear, however. If you're like me, with neither Superbike-level skills nor a slipper clutch, and you do a ham-handed job of matching engine rpm to speed while making a third-to-second downshift on a Yamaha R6, the rear end wiggles but never feels like it's going to get nasty with you. If, like me, you're a touch too abrupt on the throttle coming out of a turn on the Honda CBR1000RR and the rear starts to spin, the Qualifier minimizes the drama and maximizes the grip.

So that's my perspective — the point of view of a street rider of modest skills who gets on the track now and then.

Maybe you're a faster rider, focused mostly on track days, and you're looking for the impressions of someone with a higher skill level.

Well, you're not faster than Jason Pridmore. The AMA Superbike rider was on hand testing the Qualifiers, not because he's going to give up racing slicks for streetbike rubber, but because his Jason Pridmore Star School instructor bikes wear Dunlops. Currently, instructor bikes are shod with the D208 GPs, the track-day version, but that may change.

"I think these are better," Pridmore said after a long run on the Qualifiers. "Usually, I can get a new set of GPs to start spinning after six or seven laps. I was out there 20 laps and only the last few laps were they moving around. And it was nothing. It was easy to control."

While Dunlop's main goal was to replace the D208 ZR with a better street radial, Pridmore's comments may reveal another advantage offered by the new Qualifiers. Many advanced riders who do track days will switch between D208 GPs for track days and D208 ZRs for street use. It's a labor-intensive approach, but it maximizes both track and street performance with one bike.

The Qualifiers represent an attractive alternative for the rider who doesn't want to do that tire-changing routine. Mount a new set of Qualifiers for a track day, get performance equal to the old D208 GPs, and then leave them on and know you'll get street performance better than the D208 ZR street tires.

One final note. The Qualifiers we tested are the replacement tires that will be available at your dealer. Dunlop is also making other versions of the Qualifier to be used as original equipment on some 2006 sportbikes, and those tires may differ slightly due to specifications from the manufacturer.

The Dunlop plant is already producing Qualifiers and they should be available from your dealer or accessory store in January, 2006 in the following sizes:

Front:	Rear:
120/60ZR17	160/60R17
120/70ZR17	170/60R17
130/70ZR16	180/55ZR17
	190/50ZR17
	200/50ZR17