Ah nuts. I thought I was grasping the concept but Red's reply only confuses me more. Perhaps a photo will help. I thought brake clearance was determined by how far the center hub I marked in red is elevated off the disk.
And I thought offset was predominantly a measure of how much lip the wheel would have. For instance, in these two similar wheels below it seems the one on the right has a large offset because the mounting surface is pushed forward away from the center of the wheel and the one on the left has a smaller offset because the mounting surface is closer to the center of the wheel.
Wouldn't both these wheels have the same brake clearance based on how high the hub built into the disk is elevated?
And the left one has a deeper lip because it has a smaller offset?
Help me out Red. Why do you suggest I would only need a spacer on the rear? If anything, I thought I might only need one on the front because of the larger brake calipers.
Confused in Pittsburgh,
Tim