I'm trying to animate the wheels on this crane (not as important as the later wheels I'm drawing up right now) and I can't get a full rotation. I tried everything to my understanding to use motion transition constraints against the rail or manually rotate them in the Studio. The former never worked for me and later keeps rotation 180 clockwise, then 180 ccw, and back and forth. Can anybody explain what I need to fix? I started a fresh document with no joints for I figure I must have been screwing up on that. If anyone can, please take a look at the files and see if he or she can solve this drafting quarrel.
https://docs.google.com/open?id=0B1StefGFfwrxNER3OU5vbDlUWXlsZmI0bnpCdzR1Zw
Thanks for the help!