Oh man.. RH C2s. You're taking me back! I had the 1st gen of those on my FC... Now let me take you back further.. I had the SSR Super Fins on my 91 Integra Remember those?way back in my racing hart c2 (im sure some of those my age will recall these classic wheels) integra days; the hub rings helped a ton since my wheels were vibrating at over 100 kph (60 mph).
after the hub rings POOF... vibrations all gone.
RE: the vibration, not trying to argue here.. but i'll venture to guess the hub ring allowed you to center the wheel while tightening down the lugnuts which you were not able to do before probably due to something improper with the lug nuts or lugs themselves. With the improper taper on the lugs (especially flat, or round seats vs. acorn/conical seats) it's very easy to tighten down the wheel incorrectly (i.e. cockeyed).
In any case, I really don't have a strong opinion on this either way. Be safe everyone!
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