Hi… I'm disassembling the forks on an '85 XR100. On one side the spring tension of the assembled fork was enough to keep the damper rod from spinning and the allen bolt on the bottom of the fork came right out. But on the other side the damper rod just spins inside the fork leg. I'd like to make a tool to back up the damper rod, but looking down the fork tube I can't tell what would be the right end to put on it. Any advice on this would be greatly appreciated.