Old Tandem Roof Rack

[LCI_Brian]

About 7 years ago at a swap meet I picked up an old tandem mount for a roof rack. (It was old even then.) There is a raised front mount for the fork. The rear mount looks like it can be adjusted back and forth, so that the rear bottom bracket can sit on top the mount.

But then on the back of the mount there is a screw with a wingnut and a spring on the bottom and a plastic piece on the top. I'm trying to figure out how to use this. It looks like you get the plastic piece above the chainstays and then tighten the wingnut to hold the rear of the bike onto the bottom bracket cradle. But the plastic piece doesn't look big enough to do this and hold the tandem securely. Am I missing a piece?

Or is someone has an extra Yakima bottom tube cradle assembly lying around I could use that....

[arctos]

About 7 years ago at a swap meet I picked up an old tandem mount for a roof rack. (It was old even then.) There is a raised front mount for the fork. The rear mount looks like it can be adjusted back and forth, so that the rear bottom bracket can sit on top the mount.

But then on the back of the mount there is a screw with a wingnut and a spring on the bottom and a plastic piece on the top. I'm trying to figure out how to use this. It looks like you get the plastic piece above the chainstays and then tighten the wingnut to hold the rear of the bike onto the bottom bracket cradle. But the plastic piece doesn't look big enough to do this and hold the tandem securely. Am I missing a piece?

Or is someone has an extra Yakima bottom tube cradle assembly lying around I could use that....

Hi:
You figured out how to use the T part of the mount exactly right. I does work that way and I have been using one to hold my tandem for about fifiteen years without a problem. It is just not the fastest way to secure a tandem to a rack. After mounting the tandem you should periodically retighten the wingnut which can loosen a bit as the tandem moves as you drive.
Arctos