I just bought a bike with 1991 Shimano hubs. The picture below is the front skewer.

1. What is the thing in the middle?
2. Do I leave that thingy on when I put on the skewer?
3. If so, where is that thing supposed to go? Outside/inside the fork?
4. What danger is there if I just leave it off?

Thanks.

1. I have no idea.
2. Why bother?
3. Is it a variation on the "Lawyer's Nubs", if so: ignore it.
4. None that I'm aware of, try it and see...report back if you end up in the ER.

Can't tell for sure, but looks like a 'lawyer tab'.

You don't need it.

That was my first thought. Ditch it.

there were two, originally. They fit into buttons on the insides of the forks. kept the wheel from falling off, when you lost your mind and didn't secure the quick release lever. um, but you had to be pretty selective about that, because you had to remember to secure the tabs on the buttons, and then forget to work the quick release. I suppose you can see why they didn't last very long.

Chuck it. It won't ever be in a museum.

Thanks. You guys are the best!

But just to try to prove luker wrong, I'm going to save that piece, grease it so it won't rust, and save it in my bike parts drawer. In 20 years, hopefully I can retire off that...what do you call it..."lawyer tab?"

We called the old Schwinn versions "tinkies" because when they go loose, they went tinkle tinkle all day long and drove you mad. I can hear them rattling away to this day. Gads!