Just soak it in Dawn and water or vinegar alone overnight

It'll be fine

Use Evaporust if you want it done faster

There may be some gels that will take some of the rust off, but it looks to me as if there will be entirely too much chrome that has lifted and disappeared.

Perhaps someone else will have ideas.

davezedlee must have been writing at the same time! Seems his advice may be the way to do it.

You`ll need liquid car wax on it to keep the rust from returning fast. NO STEEL WOOL

You can still get use out if it and have it look decent, thought it won't be very pretty.

Spray the rusty part down with some CLR and then scrub the absolute bejeezsus out of it with a small wire brush like the size of a toothbrush. Rinse it often and then repeat the process.

Yes, the wire brush will leave fine scratches, but it's the only way you're ever going to cut through all that rust. You'll won't be able to see the fine scratches with the remnants of the missing chrome anyway.

Keep it as a backup or to put on a kit that you are going to sell, so you can keep your "good" hoop.

This is just my personal preference and it's what I would do if that was my hoop.

TIPS:

Small, toothbrush-like wire brushes are available at Harbor Freight or most "Brand Name" hardware stores.

A generic, spray bottle version of CLR is available at the Dollar Store and works just as well as "real" CLR. I recommend using gloves if you can. The CLR really dries out your skin and the smell remains on your skin even after multiple hand washings.

You can certainly get the rust off... but then what do you have? Might be good for a “rat rod” kit. :).

Evapo -rust is what I use.

I vote for the trash can.

What brand is it sir?