Correct me if I'm wrong but isn't this (dumpster diving) the only way to acquire these specific bikes? Other than grabbing them from debug but that isn't.. you know, "meant" to be a game mechanic. If so, it would be even more important to fix the ownership starting from finding the item.
I've noticed that once they have the bike in their inventory, the sims might ride it somewhere and sometimes then leave it on the ground and then it's not possible to drag it back to their inventory. Then it's only possible to get the bike back if you ride back to the active lot area and then the bike can be dragged to inventory.
