Greg Biffle knows he won't be perfect all season. He'll take what he can get right now. The Sprint Cup points leader continued his strong start to the season Friday by winning the pole at Bristol Motor Speedway. "I know this isn't going to last all season, but I'm enjoying the hell out of it right now," Biffle said. Read more: http://espn.go.com/racing/nascar/cu...fle-claims-bristol-pole-continue-strong-start