How to move around a Game Board

I am trying to build a Trivial Pursuit type game and I'm having trouble figuring out how to allow the user to move along the inner spokes of the wheel. Does anyone have any suggestions on how I could do this? The wheel is 42 squares around and has three spokes that cross through each other. Counting the common center square each spoke is 11 square long. I've built a function that tells the user where they can move along the outer wheel but I'm having trouble figuring the movement for the inner spokes. Any ideas would be greatly appreciated, Thanks.