Tire, Mounting
Tire, Mounting
=> [ Installing the Valve Stem ]
• Since Model Year (MY) 2005, all vehicles have new wheels with a revised contour.
• For mounting the tires, the workshop mounting device must be equipped with a tire mounting fixture intended for these new wheels.
Otherwise, there is a danger of damaging the wheel.
If the tire mounting device has not yet been modified, contact the device manufacturer.
Warm up cold tires to the minimum mounting temperature
• This applies also to ultra high performance tires (height/width ration smaller/same 45% and speed rating symbol larger than/same as V).
The minimum mounting temperature for a tire should be between 15 and 30 °C (59 and 86 °F) in the center of the tire.
• For injury-free mounting, the upper sidewall and the upper bead inside must be a minimum of 15 °C (59 °F).
• The internal temperature is called the core temperature.
• Rubber is a poor heat conductor. For this reason, a cold tire must be exposed to a temperature controlled environment until the inner rubber layers have warmed up to at least 15 °C (59 °F).
• The tire surface temperature during the warm-up phase is not a measure of the inside temperature.
• So that the cold tires warm up as quickly as possible, never stack them one on top of the other; store them separated from each other so that the warm air can "circulate" around them.
• Never us a room heater or a hot air gun to warm up tires because the surface temperature will heat up very quickly to a critical temperature.
• To prevent damage, only warm water or warm air (maximum 50 °C (86 °F)) can be used to warm up a tire!
• If cold tires (below 0 °C (32 °F)) are brought into a warm room (above 0 °C (32 °F)), a layer of ice will start to form on the tires. This layer of ice means that humidity in the warm air is condensing on the tire.
• Once the layer of ice starts to melt, water will start to build. Wipe up the water with a cloth so that the warming process does not slow down.
Warm-Up Time
• Using the example of a room temperature of at least 19 °C (66.2 °F) and a tire temperature of 0 °C (32 °F) or higher, the tires should be stored for at least 2 hours at a temperature of at least 19 °C (66.2 °F).
• If the room temperature is a minimum of 19 °C (66.2 °F) and the tire temperature is below 0 °C (32 °F), then the tires should be stored for at least 2.5 hours at a minimum room temperature of 19 °C (66.2 °F).
Recommendations
• If possible, let the tires stand in the workshop for 1 day before mounting them
• Store the tires as high as possible on an insulated surface, such as a pallet or something similar
• Position the tires so that they can be "surrounded" by the warm air
• Wipe off the sweat
• Never heat the tires with a room heater or a hot air gun!
Installing the Valve Stem
• Make sure wheel is clean.
- Use the valve fitting tool (VAS 6459) - 1 - to install a new valve stem.
- Remove the valve stem insert.
- Inflate the tire to approximately 3 to 4 bar (43.5 to 58 psi), the tire bead must audibly slide over rim hump.
- Install the valve stem insert.
- Correct the inflation pressure to the specified pressure.
- Balance the wheel.