Quick Quiz on Tires/Wheels

Kirby · Jun 3, 2004

One of the car mags had several articles on tires and wheels. Here's two questions, who knows the right answers? (If you saw these articles, let the others post some answers first!)

1. If you have a major tire failure/blowout at highway speeds you should:
A. Coast
B. Brake gently
C. Floor it
D. Brake hard

2. Increasing wheel size with an appropriate lower profile tire, provides better handling and performance - True or False?

BMW_FaNaTiC · Jun 3, 2004

1)c
2.)True

Kirby · Jun 6, 2004

Kirby said:

1 - C is correct. Michelin says to floor it to maintain speed until you have control, then gently get off the road safely.

2- True, up to 18"; False for anything bigger. They did a test of various wheel sizes on the same car. Above 18", handling became LESS consistent and stable. The additional weight of the larger rim actually reduced accelleration time and and increased braking distance. Wheels over 18" inches may look good, but that's about it.

This article was in Motor Trend last month.

Dinan55 · Jun 6, 2004

Kirby said:

1 - C is correct. Michelin says to floor it to maintain speed until you have control, then gently get off the road safely.

2- True, up to 18"; False for anything bigger. They did a test of various wheel sizes on the same car. Above 18", handling became LESS consistent and stable. The additional weight of the larger rim actually reduced accelleration time and and increased braking distance. Wheels over 18" inches may look good, but that's about it.

This article was in Motor Trend last month.

How come race cars have 19" wheels? Well some do, I think?

Kirby · Jun 7, 2004

They were testing street cars, tires and wheels. Several important differences:
- Race car suspension/geometry is designed for larger wheels/lower profile tires. Street car suspension is designed for the wheel size(s) the that were offered by the manufacturer.
- True race car wheels/tires are lighter than any street car wheel/tire. They are designed to be strong for racing stresses (hub, spokes), but are lighter because the rim itself is thinner and lighter. No need to worry about rim strength for potholes, curbs, etc. They also use higher strength, lighter weight alloys to get the job done.

dzervit · Jun 7, 2004

1. D

Weeeeee!!!! Round and round we go!!

Bryan330i · Jun 9, 2004

dzervit said:

Hahahahaha [rofl]

I blew it on 1. I would have said brake gently or coast.

Kirby · Jun 10, 2004

For the test, Michelin has a vehicle rigged with a "blowout on demand" device to pop the tire. They let the reporter try it as they recommended (floor it) but they refused to let him try it with braking. They said their testing proved it was too dangerous!

Tigas Bud · Jun 10, 2004

Had a rear tire blow on mine on the freeway last summer. Passenger side rear at about 80 mph, car stayed in control fine and I slowed and moved to the right shoulder. All that happened is an (insert your descriptive noun) in a newer Buick Riviera pulled over shortly after me and I asked if he lost a tire, too? Thinking maybe there was something in the road. No, he wanted me to buy him a new front window for throwing stuff at his car and to kick my (insert body part here). Still waiting for the kicking but not loosing sleep over it.