SKEDSOFT

Automobile Engineering

Introduction:

Because cars have been downsized in recent years, space and weight have become major concerns for vehicle manufacturers. For this reason, many car manufacturers have marketed cars with compact spare tires to save weight and space.

 

Compact, high-pressure, minispare tire:

  • The high-pressure minispare tire is the most common type of compact spare.
  • This compact spare rim is usually four inches wide, but is one inch larger in diameter than the other rims on the vehicle.
  • The compact spare rim should not be used with standard tires, snow tires, wheel covers, or trim rings. Any of these uses may result in damage to these items or other parts of the vehicle.
  • The compact spare should be used only on vehicles that offer it as original equipment. Inflation pressure in the compact spare should be maintained at 60 psi (415 kPa).
  • The compact spare tire is designed for very temporary use until the conventional tire can be repaired or replaced. Limit driving speed to 50 mph (80 kph) when the high-pressure minispare is installed on a vehicle.

 

The space-saver spare tire must be inflated with a special compressor. Battery voltage is supplied to the compressor from the cigarette lighter. This type of compact spare should be inflated to 35 psi (240 kPa). After the tire is inflated, be sure there are no folds in the sidewalls.

The lightweight-skin spare tire is a bias-ply tire with a reduced tread depth to provide an estimated 2,000 miles (3,200 km) of tread life. This type of spare tire is also designed for emergency use only, and driving speed must be limited to 50 mph (80 km/h) when this tire is installed on a vehicle. Always inflate the lightweight-skin spare tire to the pressure specified on the tire placard.