Dunlop’s Sportmax GP-A Pro is the company’s first bi-directional, N-TEC, DOT-labeled road racing tire and the replacement for the Sportmax D211 GP-A. Designed to give the ultimate motorcycle race tire performance in both dry and wet conditions while conforming to DOT street tire regulations.
Dunlop GPA Pro Sportmax Tires Technical Specs
120/70 ZR 17 Dunlop GP-A Pro Front Tire
- Recommended Rim range (3.50-3.75), Best Rim (3.50)
- Width (122mm/4.80″)
- Diameter (605mm/23.82″)
- Available Compounds: 7455 Med, 8477 Med+
- Suggested Hot Tire Pressures: Hot on the warmers 34-36psi
- Suggested Cold Tire Pressures: Cold 30-32 psi
160/60 ZR17 Dunlop D211 GP-A Pro Rear Tire
- Recommended Rim range (4.5-5.0), Best Rim (4.50)
- Width (167mm/6.5″)
- Diameter (633mm/24.9″)
- Available Compounds: 7455 Med
- Suggested Hot Tire Pressures: Hot on the warmers 28 psi
- Suggested Hot Tire Pressures: Cold 32 psi
190/60 ZR17 Dunlop GP-A PRO Rear Tire
- Recommended Rim range (5.50-6.00), Best Rim (5.50)
- Width (190mm/7.48″)
- Diameter (657mm/25.8″)
- Available Compounds: 2662 Soft, 7455 Med, 8477 Med+
- Suggested Hot Tire Pressures: Hot on the warmers 22-25 psi
- Suggested Hot Tire Pressures: Cold 18-22 psi
Note: For street riding, follow the motorcycle owner’s manual for air pressure recommendations. For track or race use, optimal air pressures vary with track conditions but general suggested air pressures are above.
THE DUNLOP ADVANTAGE
Dunlop’s commitment to advancing the state-of-the-art in road race tires never ceases. As the exclusive spec tire provider in AMA Pro Racing since 2009, Dunlop can access the best riders in the country to inspire continuous tire development. The new machinery and manufacturing capabilities added to Dunlop’s Buffalo, New York manufacturing plant—the only motorcycle tire plant in the U.S.—gives Dunlop the capacity and flexibility to develop and manufacture new tire technologies. The Dunlop Proving Grounds in Huntsville, Alabama—the only motorcycle-only tire testing facility in the U.S.— gives Dunlop dedicated development advantages in various conditions. This combination—a close working relationship with top road racers, a high-tech manufacturing plant and a dedicated proving grounds—add up to a unique development advantage that created the revolutionary GP-A Pro.
Progress on the racetrack is easy to measure: Stopwatches don’t lie. So to help test the new bi-directional Dunlop Sportmax GP-A Pro DOT road race tires, Dunlop enlisted AMA Pro Daytona SportBike stars Cameron Beaubier and Garrett Gerloff. The results speak for themselves.
In 2013 at Road America, back-to-back testing of the existing Dunlop D211 GP-A race tire and the prototype Dunlop GP-A Pro saw Gerloff chop 1.78 seconds off his lap time—a huge leap forward. Beaubier, who became the 2013 AMA Pro Daytona SportBike champion, pared down his lap times as well. But he also demonstrated the advantage of the GP-A Pro in more dramatic fashion, dragging his elbow while cornering—something he said he had never done before at Road America.
“The new tire offers better edge grip,” said Beaubier. “I feel much more confident at full lean, and the bike seems to track better under braking.” Higher traction at full lean—it’s no coincidence the same compound and construction used in that prototype tire ended up in the production GP-A Pro
Dunlop’s commitment to expanding the performance envelope of this new race tire did not stop with higher grip. Dunlop also offers a feature that allows this tire to last longer by making the rear tire bi-directional.
Racetracks typically put more wear on one side of the tire than the other. The
bi-directional Dunlop GP-A Pro rear tire can be flipped in rotational direction to get more laps
out of the tire. This versatility helps club racers and track-day riders stretch their tire budget. But it also pays off at the pro level. AMA regulations allocate five fronts and seven rear tires for a double-header race weekend. Now, using bi-directional tires, teams can run a practice session with a “refreshed” tire that has been flipped around and save a new tire for timed qualifying, for example. With Dunlop’s innovative bi-directional technology, riders of all levels can benefit.
JOINTLESS TREAD APPLICATION
The Jointless Tread application is key to the GP-A Pro bi-directional construction. Using the process pioneered on the bi-directional KR451 slick race tire, sophisticated production machinery in Dunlop’s Buffalo, New York plant winds the tire tread onto the carcass in a continuous strip allowing the tire to be run in both directions.
COMPREHENSIVE DESIGN ADVANTAGES
The GP-A Pro features many innovative tire construction technologies developed by Dunlop in recent years, including:
—Carbon Fiber Technology (CFT)
—Jointless Tread application
—N-TEC radial tire construction
—Continuously wound Jointless Band (JLB) aramid-fiber belt
—Continuously wound hex-beads
—Intuitive Response Profile (IRP)
SYMMETRICAL TREAD PATTERN
After the tread rubber is wound onto the tire carcass, this uncured tire goes into a mold that creates the tread pattern and gives the tire its final shape. Although the front tire is not reversible—unnecessary since typical track wear generally sees a ratio of about two rear tires used to one front tire—the GP-A Pro incorporates a new, symmetrical tread pattern on both front and rear tires, which was developed through real-world race testing at tracks around the country and the Dunlop Proving Grounds in Huntsville, Alabama. Compared to the previous-generation D211 GP-A, the “land-to-sea” ratio of the GP-A Pro tread pattern places appreciably more rubber down in the working area of the tires to offer enhanced performance.
INTUITIVE RESPONSE PROFILE
This rear-tire technology incorporates steep sidewalls for a unique tire profile that helps enhance steering response, feedback to the rider and overall cornering stability. Intuitive Response Profile (IRP) offers greater latitude in line choice while cornering and offers amazingly linear steering at various lean angles.
With the Dunlop GP-A Pro, Dunlop not only delivers a higher level of performance for professional riders in AMA DOT-class racing for 2014, bi-directional tire technology gives club racers and weekend track riders longer lasting tires. More grip and more laps—the GP-A Pro delivers both.
Beneath the tread, the carcass incorporates many of Dunlop’s high-tech advancements including hybrid N-TEC construction. N-TEC combines the benefits of compliant cut-breaker construction with stiffer, continuously wound aramid-fiber Jointless Band construction, and was first designed specifically for racing applications.
CONTINUOUS WOUND HEX BEADS
Like the Q3 and D211 GP-A, the GP-A Pro also features Dunlop’s continuously wound hex beads. This hex bead offers enhanced feel as the tire nears its cornering limits. They are also light and strong, which offers a benefit to steering response and cornering stability.