AGV Backmarker: Learning to Love Las Vegas

The new Q2 then, is the top street-recommended tire. The executive summary of the pitch for the new tire came down to this: the front tire was a tweaked version of the Qualifier (better in every way, we were assured, but fundamentally similar to its predecessor, which Dunlop felt was still a very competitive product). The rear was extensively re-profiled, taller and with “steeper” shoulders for a larger contact patch at maximum lean angles. Dunlop told us that the new tire offered 15 percent-better drive and traction grip than the old Qualifier, and 25 percent more corner stability. Those are impressive numbers, although they don’t of course translate into 15 or 25 percent quicker laps—it’s more like 4 percent, which is still very significant. They shared data-logging from a comparative test at Virginia International Raceway, where the new tires (mounted on a GSX-R1000 test mule) accounted for about a 3-second improvement in lap times, with much-improved peak lateral g-forces.

The rear profile, something Dunlop calls Intuitive Response Profile, is taller in the middle, with steeper shoulders. They say the shape allows for easier turn-initiation and makes it easier to adjust lines in mid-corner. As expected, it’s a multi-compound tire with a tougher center compound (that helps it achieve reasonable mileage) and softer shoulders. Dunlop’s Mike Manning characterized the compounds by saying, “The center compound is similar to the Qualifier, while the edge compound is…. from the same family as the GP-A.” Presumably with somewhat better wet grip, as one racer familiar with the GP-A’s performance in damp conditions told me it was terrible. (If the AMA declares a race to be wet, riders can—and almost always do—elect to run Dunlop full-wet race tires.)

One of the key objectives of the new shape and construction was not just a larger contact patch, but one with better pressure distribution.

To achieve that, Dunlop designed a revised aramid (aka Kevlar) belt. Dunlop refers to this belt as having Jointless Belt construction. Other tire manufacturers help to shape and structure their tire carcasses by variable windings in this belt. The Dunlop JLB method is different: the belt is wound the same across its width, but is sized and shaped in such a way that after the tire cures to its final shape, the belt is stressed. That makes the carcass stronger and more able to withstand stress without distortion. (Tire design is always a compromise between compliance—the ability of the tire to absorb irregularities in the road surface—and stability—the ability of the carcass to hold its shape under the stresses of braking, cornering, and accelerating.)

Other changes include lighter-weight 12-wire bead, to minimize gyro effects and lighten steering effort.

The Qualifier was almost a slick to begin with, but the Q2 has a slightly higher land-sea ratio. The tread pattern has a familiar Dunlop “look” that they call a “cosecant curve.” The shape of the tread not only looks cool, it aligns the grooves with the forces applied to the tire, to minimize distortion and wear, while still providing some water-clearing ability. Polymer chemistry was tweaked to improve wet grip.

Right now, Dunlop Qualifiers are not OEM fitment on many bikes that I can think of—the exception being Suzuki’s grossly under-rated/over-powered B-King. The Qualifiers work great on that beast, but Dunlop was coy about the prospect of the Q2 being chosen by manufacturers for OEM use. They’re talking about it as a replacement tire only. Although it’s aggressive riders of liter bikes who chew up the most tires, it will be offered in a wide range of rear widths, from 160 to 200, for use on everything from the Suzuki Gladius to the Honda CBR600RR to the Kawasaki ZX-14.

Although tire guys are loathe to talk about the mileage riders can expect to get from tires, Dunlop did offer up this: the goal with the Q2 was to beat the Qualifier in every measurable way, including wear. What this probably means is that even aggressive liter-bike riders should get at least a couple of thousand miles out of a rear tire, and that someone riding a 600 as a commuter can hope for 5,000 or so. Fronts will last quite a bit longer, of course.

Note that the operating temperature range of the Q2 is wide. Dunlop engineers told me it was intended to optimize performance between 50 and 100 degrees. By inviting us to test in Nevada in late June, they pretty much guaranteed we’d have no trouble getting them up to temperature, but also ensured we’d have no chance to try them in cool, damp, or wet conditions. Riders who ride on cold roads in the “shoulder season” in northern states (or my homeland of Canada) and riders up in the rainy Northwest would be smarter commuting on the Sportmax Roadsmart, which was specifically compounded for cold-wet grip.

Dunlop didn’t give us pricing, but they told us that Q2s would be available, at least in key sizes, by the end of the summer. So, if you’re a Dunlop man (or woman) and you’re a 1-2,000 miles short of needing replacement rubber, your timing’s about right.

That’s the technical side of this story, so I’ll wrap up this week’s AGV Backmarker here and save the track impression and the juicy tire-guy gossip for next week’s edition. Suffice to say, for now, that the tires are good enough that even if you’re not a Dunlop woman (or man—how’s that for even-handedness?), you might think about switching brands after reading next week’s column.

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