Conrad's time machine

When Tom Kolczyskrenski got his discharge papers from the Air Force, he decided to look up his old pals—and the world would never be the same. At one time, the oddly mismatched trio had been roommates, then they'd gone their separate ways. Tom, for lack of money, enlisted in the Air Force to learn electronics. The other two had finished college, lan McTavish going into mechanical engineering and a job with GM, and Jim Hasenpfeffer into behavioral science, leading to his having gotten a Department of Defense grant to—this is serious stuff, now—study social interactions in motorcycle gangs. So the three set out to be their own motorcycle gang. But these easy riders had barely begun to closely observe their own interactions when they ran across a strange perfectly hemispherical hole in the ground where a house used to be, with everything that had been in the sphere of influence slowly materializing in bits and pieces in the surrounding area. And they found the plans for the machine that had done this, and were sure they could duplicate it and get rich. But before long they would be wishing they had kept on being the three musketeers on bikes, instead of the three stooges of time travel....