Watch for These Marks

Watch for These Marks  (c. 1943) 

Source: U.S. National Archives and Records Administration


Watch for these marks[1] They mean synthetic rubber

  1. On a tire a red circular spot bearing the letter "S" and a number, and a red or blue stripe around the base or a tube show synthetic rubber is used.

How to install synthetic tires

1. Remove rust and scale from rim—an important first step.

2. Remove dirt and grit from inside of casing, and check inside and out for cuts, breaks, rough spots, nails, glass, and the like.

3. Inflate tube only to a point where it starts to round out.

4. Dust the tube completely with talc or soapstone.

5. Insert tube in casing and mount on rim. Be careful not to pinch, pull, or tear tube.

6. If flaps are used, dust them completely with talc or soapstone, and make sure they are centered and free from wrinkles.

7. On drop center rime, be sure beads are out of well before inflating.

8. Inflate tire partially. Then deflate to ease localized strains and permit tube to readjust itself. Then inflate to specified pressure. This new two-step inflation procedure is of vital importance.

9. Measure tire for size. Remember, dual tires and all "driven" tires must not vary by more than 3/4 inch in circumference or 1/4 inch in diameter.

10. Install tire on vehicle. Observe mounting instructions for directional tires.

How to maintain synthetic tires

1. Keep tire pressures exact at all times.

2. Watch for cuts or breaks, and for rapid wear due to wheel misalignment.

3. Have tires repaired or recapped in time.

How to drive on synthetic tires

1. Do not drive faster than 35 miles per hour.

2. Do not overload vehicles.

3. Steer around rocks, ruts, curbs and other obstructions.

4. Drive smoothly. Avoid quick starts, stops and skidding.

Synthetic rubber tires and tubes will give long life and dependable service provided you install, maintain, and operate them according to these special instructions

This work is in the public domain in the United States because it is a work of the United States federal government (see 17 U.S.C. 105).