[alt63bird]

Originally Posted by dmsfrr

I'm not sure I understand your question.

The smaller hub caps, full wheel covers?
Some full wheel covers do lose their grip over time and fly off when cornering.
Bending the tabs on the back side for a tighter fit may take care of it.
I've seen other folks comment that wheels made before the mid 60's flex more than newer versions and that could be part of the problem.

The tread on the tire?
Tires do age-out.
Most tire shops won't service one over about 8 yrs old, due to failures and legal liability.

That pic of the Kelsey-Hayes wire wheel (or look-alike - I'm not going to bother counting spokes) reminds me of the tires on my '63 T-bird Sports Roadster - were about 28 years old when they 'let go' like that three years ago - tread came off the carcass of one of the rear tires but thankfully no damage to the car. As for the '55's rims, I would suspect that with the narrow profile that they will flex more with radials and throw full wheel covers. Even the 14" solid-center rims on my '63 T-bird allow the full covers (especially the ones with spinner centers) to 'walk' and shift - using solid steel valve stems/extensions helped to keep them from rotating on the rim, but after a few drives I walk around and check to see that they're seated.