Sprint Cup drivers say they are concerned about tires for Sunday’s race as the Goodyear tires are leaving marbles of rubber on the track and have not rubbered in the Martinsville Speedway.
The .526-mile racing surface is a mix of asphalt with concrete corners. Goodyear brought a
different tire to prevent grating on the left-side tires as they slide across the concrete. Softer right-side tires were selected to add grip and compensate for the change in grip of the lefts.
Tire issues, which surfaced Friday, are not rare for the track. Some teams saw significant wear, but it’s not necessarily an issue about wear as much as grip and getting the track rubbered in to avoid the marbles.
"The tire is not failing," NASCAR Sprint Cup Series director John Darby said. "The tire has some different drivability characteristics that everybody is dealing with in both the truck series and Cup series.
"It’s a combination of a little tougher left side and a little softer right side; it makes the cars feel different. It’s really hard to make a judgment either way right now until we see 500 laps of racing."
If the tires continue to marble, it will make passing difficult because drivers won’t want to take a higher line in an attempt to advance through the field in Sunday's Goody's Fast Relief 500.
"The tire is really crappy, but that’s just the way it is," Dale Earnhardt Jr. said. "There’s not much they can do about it. … Once you get in the marbles, you ruined that set. There’s no way to get them off.
"We don’t go fast enough here to really get them off. It was real messy all day (in practice)."
Because Cup drivers had both practice sessions on Friday and were on the track for only two laps of qualifying Saturday, they hope that the track rubbered in during Saturday afternoon’s Kroger 250 Camping World Truck Series race.
"We have seen (these issues) before here on a clean racetrack," Jeff Gordon said. "I’m just surprised it never really laid rubber. … Great intentions (by Goodyear), and we all want that more grip.
"But we’re really struggling a lot with some really bad loose conditions, getting in the corners and getting off the corners. I’m just glad we weren’t alone in that."
Kyle Busch said the tires are wearing out in 25-30 laps more than usual but not yet to the cords. He said it feels as if they’re just spinning without grip. Busch’s Joe Gibbs Racing teammate Joey Logano crashed his primary car when it just spun around on him during practice Friday.
"They just go away really quick," Busch said. "It’s unfortunate we’re not seeing rubber down—that’s what we’re worried about."