12 Vehicle Wheels and Tyres

What is this special pneumatic tool called associated with tyres?

• Tyre pressure inflator and gauge
• Tyre pressure inflator
• Tyre pressure gauge
• Tyre gauge

The principle functions of a tyre are:

• Contain a volume of pressurised air

• To transmit traction and braking forces

• To provide directional stability

• To supplement the vehicle's suspension

Road wheels are required to be:

• Lightweight, to reduce unsprung weight and therefore improve road holding.

• Strong, to resist normal loading and accidental damage,

• Rigid, to resist bending or deflection when cornering.

• Retain the tyres, to avoid the tyre coming unseated and deflated.

A tyre size designation is 205/55 R 17. What does the 205 indicate?

• The tyre is 205mm in height.

• The wheel is 205mm in height

• The width of the tyre tread is 205mm

• The width of the wheel is 205mm

While carrying out a pre-use inspection on this tool, you find a perished and split hose. What action do you take?

• Carry out a repair by removing the clip and shortening the hose.

• Carry out a repair by removing the clip and replacing the hose.

• Take the tool out of service and report it to my Manager.

• Carry on and use it until it breaks completely.

The purpose of tyre tread is to displace water to prevent aqua planing.

• False

• True

A tyre size designation is 205/55 R 17. What does the 55 indicate?

• The 55 is a measurement of the sidewall size in mm.

• The 55 is a measurement of the sidewall size in inches.

• The 55 is called the Aspect Ratio, a measurement of the sidewall size in mm.

• The 55 is called the Aspect Ratio and is measurement of the sidewall size in a percentage of the tread width.

On a 205/55 R 17 tyre, the 'R' informs you that the tyre has what type of construction?

• Radial
• Rapid

• Ribbed

• Radius

 

A tyre's size designation is 205/55 R 17. What does the 17 indicate?

• The tyre fits a 17" wheel

• The tyre has 17mm of tread.

• The 17 shows the tyre has an Aspect Ratio of 17%

• The tyre has a speed rating of 117 mph

As time has progressed, the aspect ratio has changed from 100% to as low as 35% on some modern vehicles, why?

• The low profile looks better.

• The lower profile reducing the sidewall flexing and therefore reducing slip angles

• The tyres run at a lower pressure

• Bigger brakes can be fitted