Eric Bostrom finished seventh in today’s AMA Pro American SuperBike race at Virginia International Raceway. Up front, Rockstar Makita Suzuki rider Tommy Hayden made a last-lap draft pass to beat Bostrom’s older brother, Ben, riding a Pat Clark Motorsports Yamaha YZF-R1, to the finish line by .005 seconds. Team Graves Yamaha’s Josh Hayes, who led most of the 23-lap event, was a close third.
Bostrom, who won the Superbike race at VIR in 2002, used the waning seconds of final qualifying on Saturday morning to post the fourth-quickest time of the session–good enough for the final spot on the front row alongside Hayes, Hayden and his pole-sitter brother, Ben. This was a significant improvement from Friday, when, during morning practice and afternoon qualifying, Bostrom hovered just inside the top 10 as he struggled to refamiliarize himself with the rolling, 18-turn, 2.25-mile racetrack.
With 4:32 remaining in the Q2, run Saturday morning in cool, overcast conditions, Bostrom pitted. “What do we have to do to get on the front row?” he confidently asked crew chief Richard Stanboli. At the time, Bostrom was sixth-quickest, having posted a best lap of 1:25.589. He re-entered the track with just 3 minutes to go–time enough for just two fast laps. After a 1:31.414 out lap, he dropped to a 1:25.315. His final lap was a 1:25.647. This is the best qualifying position to date for Team Cycle World Attack Performance Yoshimura Suzuki.
Bostrom accomplished this feat on a soft-compound (6704) Dunlop ATQ08 rear tire. For the race, he used the harder, medium-compound (6680) option. Of the top three finishers, only Hayden chose the soft rear. “[The asymmetrical ATQ08] was developed for tracks with lots of high temperatures and time spent on the right side of the tire,” said Dunlop’s Sebastian Mincone. This same tire was introduced at VIR last year and used for the first time this season at Road Atlanta. Bostrom also stuck with the medium-compound front tire.
Stanboli and mechanics Jim ”JJ” Matter, Dan Schwartz and Todd Fenton had worked flat out on Friday morning to fit our A bike with a new, larger-capacity “works” radiator on loan from Yoshimura Racing and the B bike with a custom wiring harness to run a second MoTec engine-management system. (Stanboli was awake well into the night on Thursday finishing the harness.) With the further addition of newly baffled lightweight aluminum gas tanks, engine spec and radiator type are now the only significant differences between our two GSX-Rs.
Chassis setup continues to evolve. At VIR, Ohlins tech Matt Hickson installed lighter-weight fork springs (from 9.75 to 9.5 Nm) and firmer compressions settings (CA8 to CA9) in the fork. During the two-week “break” between Laguna Seca and VIR, Stanboli and Ohlins’ Mike Fitzgerald had worked on a new fork combination–the “A” in “CA9″ stands for “Attack.” Initial shock settings were as follows: 120 Nm spring, C7R5 valving, 10mm preload. “The fork-spring change was positive all the way around,” said Bostrom midway through Q1.
One click each of compression and rebound in the fork followed, along with a 2mm increase in rear ride height. Back in the garage, Stanboli also continued to play with steering geometry, increasing dynamic trail for “more feel,” and upping shock “free” sag, the latter change to counter Bostrom’s complaint that the shock was “topping out” halfway down the front straightaway. As always, a perfect setup remains elusive.
Watching Saturday’s race unfold, which saw Bostrom get a slow start and slip as far back as ninth place, Stanboli said, “Eric needs more time to mix it up. We’re asking a lot of him just three races [into the project].” After the checkers, having removed his gloves and helmet, Bostrom exclaimed, “Tomorrow! Tomorrow! Those guys are running it in so hard on the front tire; I’m not used to that.”