I read this book back in the early 1990's and it was a fantasy novel depicting a nordic-viking type setting with no science fiction. I'm not even sure if there was magic involved but there may have been. I remember one scene when the three close friends whose one friend was handicapped. The two other friends grabbed their respective handicapped friend to jump over the gorge with them. The instructor mentioned as a side joke that even though their friend was handicapped, he still had the biggest penis of them all.