44 Tyres
WM 4400IN Tyres
General information on mounting tyres
General
Information
- Always use new rubber valves when changing tyres.
- The metal valve only needs to be replaced in certain cases. -> 443219 Removing and installing wheel electronics Service and Repair
- When fitting tyres, the direction of rotation and the inner and outer sides should be noted.
- Only use TIP TOP Universal or Contifix tyre fitting paste.
Before mounting the tyres on the wheels, check for damage (cracks, dents etc.) as well as radial and lateral runout. Maximum permissible radial runout and lateral runout of the light alloy wheels = 0.7 mm. Maximum permissible radial runout and lateral runout of the wheel with tyre = 1.25 mm. Values less than 1.0 mm - better around 0.5 mm - are desirable.
When mounting tubeless tyres, check the sealing surface of the tyre and the disc wheel for cleanliness and any signs of damage. Bear in mind here that the bead base performs the sealing function on tubeless tyres. When mounting the tyre beads, use only the specified tyre mounting pastes. The following can occur if an unsuitable mounting paste is used:
- Twisting of the tyre on the rim
- Fracture of the bead core during mounting if the seating pressure is too high
- Damage to the tyre bead
- Damage to the rim surface by aggressive substances.
If Contifix is used, apply sparingly to the tyre beads (due to risk of the tyre turning on the wheel). If possible, the vehicle should not be driven for 24 hours after tyre mounting or matching.
Information
- Customers should be informed that the full performance of new or newly mounted tyres is achieved only after a distance of 100 to 200 km (60 to 120 miles) has been driven. Extreme driving manoeuvres (acceleration, braking) should be avoided.
- The absolute limit on how far the tyre can turn on the wheel must be regarded as 20 mm. Furthermore, this will worsen the result of optimum balancing.
- Mark the relative positions of the tyre and wheel for reference.
In order to optimise rolling smoothness, it is a good idea - and necessary in individual cases - to mount the tyre in a favourable position with respect to the wheel (matching).
Uncontrolled matching
Turn the tyre on the wheel by 90° or 180° if necessary in order to achieve an acceptable value with regard to rolling smoothness (true running, imbalance and distribution of balance weights).
Controlled matching
Using a balancing machine with matching program. In most cases, this produces an even better result with regard to the rolling smoothness (true running, imbalance and distribution of the balance weights) than can be achieved with uncontrolled matching.
Installation
CAUTION
Sometimes a high tyre seating pressure is required (max. 4 bar. This must not be exceeded.)
- Personal injury may occur in the event of tyre or wheel damage (due to the coincidence of several unfavourable factors)
-> The tyre must therefore be filled in the filling cage.
Tyre filling cage
- After mounting the tubeless tyres, inflate them without valve insert to a maximum of 4.0 bar gauge pressure to ensure they are seated properly on the wheel. At the latest when the pressure reaches 4.0 bar, the tyre beads must pop out of the deep bed and over the hump of the wheel shoulder in order to avoid fractures of the bead core. If necessary, interrupt the process and coat all necessary surfaces with lubricant (tyre mounting paste) again. Then repeat the process. Screw in the valve insert and set the specified tyre pressure.
If new tyres are to be mounted or the tyres of one axle are to be replaced, tyres of the same make and with the same specification code must always be used on each of the two axles. If tyres are replaced on one axle only, the different tread depth in relation to the other axle can cause a noticeable change in the handling the driver has become accustomed to. This is especially true if new tyres are mounted on the rear axle. This effect decreases with increasing tyre mileage.
Information
- If a tyre is damaged and it cannot be determined with absolute certainty that there is no ply damage - with all of its consequences - or if the tyre was thermally or mechanically overloaded due to a loss of pressure or other prior damage, we recommend replacement of the tyre in question for safety reasons.
- When replacing a tyre on an axle, make sure that the tread depth of the new tyre does not differ from that of the other tyre by more than 30 %.
- Repairs to the tyres are not permitted nor is the use of inner tubes in tubeless tyres.
- When replacing summer tyres, pay close attention to the tyre specification number.
The overview of summer and winter tyres is included in Technical Information (TI), Group 4. When replacing summer tyres, pay close attention to the tyre specification number for the same make of tyre. The specification characters (for example N0) distinguish the summer tyres specially authorised by Porsche from other models of the same tyre type and size.
Balancing weights
Type of balancing weights: Adhesive weights as used previously (no special version necessary). Also refer to the spare parts catalogue.
Attach both weights to the inner side -arrows-.
Information
- Observe program selection and operating instructions of the balancing machine.
Navigation system
After a wheel change, the full locating accuracy is attained only after a journey of approx. 50 km (if possible on the motorway and at a speed > 60km/h). Furthermore, high wheel slip (e.g.: wheel spin) can result in temporary incorrect positioning.
Wheel storage
Tyres must be stored in a cool, dry and dark room with adequate ventilation. They must never come into contact with fuel, oil, grease or chemicals. Complete wheels can be stacked for storage. It is advisable to increase the tyre pressure by 0.4 bar.
If the tyres are not mounted on wheels, store them in the vertical position. Tyres stored in vertical position should be turned every two weeks in order to prevent excessive flattening. If the tyres are stacked in horizontal position, they will become severely deformed and cannot be seated in the rim flange easily when mounted.
Tyres age due to physical and chemical processes, which can impair their function. If they are stored for an extended period, they will harden and become brittle faster than tyres that are in continual use. Hairline ageing cracks can occur on older tyres. If tyres are in use, the kneading action activates the plasticizer in the rubber and thereby prevents hardening and cracking.
Tyre age
Information
- Tyres should not be older than 6 years. Not even the emergency spare wheel.
The age of the tyre can be determined from the manufacturer's code, which is placed behind the DOT code on the tyre sidewall. The date of manufacture (the last four digits) is located at the end of the code).
Example
