Chasing Alliecat — Rebecca Fjelland Davis

Dumped with relatives in a small Minnesota town for the summer, Sadie Lester is relying on her mountain bike to save her from total boredom. Then she meets Allie, a spiky-haired off-road mountain biker who's training for a major race. Allie leads Sadie and Joe, a cute fellow cyclist, up and down Mount Kato, and the three become close friends. But the exhilarating rush comes to a halt when they find a priest in the woods, badly beaten and near death. After calling for help, Allie disappears from their lives.

As they search for Allie and try to find out why she left so suddenly, Sadie and Joe discover more about Allie's past, including her connection to the priest. Only on the day of the big race does Sadie finally learn the complete, startling truth about Allie--and the terrible secret that forced her into hiding.