Getting 4" High Traction Wheel to touch the ground

I was “cadding” a new drive train for my robot when I realized that the 4" high traction wheels were slightly smaller than the 4" omnis and they did not touch the ground when in the middle of a drive train. Is there any way to make them touch the ground? @_@

This issue has been raised on the forum previously. For some of the solutions people came up with see
(You are looking for about midway down page 6 and page 7)