Tire fitting

The following assembly and dismantling procedures refer to the 17-inch Cup and Cup Design wheels with asymmetric hump.

Notes / tools

- For mag wheels (911 Carrera RS), pay particular attention so as not to damage the paintwork, including the hump area. If required, cover the rim flange with adhesive tape after the pressing off stage.

- To remove / fit a tire, a tie-down tool -Special Tool 9539 - is required. In addition, the tire lever should be flattened along its front face and should then be rounded (arrow).



Tire assembly

- Fit wheel to assembly stand and coat inside of wheel and both tire beads with tire assembly compound. Replace the valve whenever a tire is fitted or refitted. Note

Recommended tire assembly compound: Use only Contifix or TIP TOP Universal, Part No. 593 0601 (3.5 kg can).

- Set assembly tool to correct clearance.

- Set assembly tool to correct clearance.

- Fit first tire bead in the usual manner.


The asymmetric hump changes its cross-section across the circumference. The following points must therefore be observed when fitting or removing a tire.



- When starting to fit the second bead, the assembly arm should be located opposite the valve. Then place the second bead as flat as possible onto the wheel, guide it across the assembly head and tie it down with Special Tool 9539, keeping it offset by approx. 90 to 120 deg.

While performing the turning motion and fitting the second bead, use a second tire lever and Special Tool 9539 to locate the tire bead in the drop center.


- When combining 255/40 17-inch tires with 8-inch wheels, the additional tire level must be placed below the hump.


- When inflating the tire, the beads must jump over the hump at a positive pressure of 4.5 bar at the latest.

The bead still located in the drop center must therefore be positioned opposite the valve (flatter hump section) when the tire is pumped up. If required, rotate the tire accordingly and coat with assembly compound again.

Removing the tire

- Adjust assembly head as for tire fitting (Fig. 1014-44).

- When pressing off the tire, start at the valve since the levering force required in this area is somewhat lower.

Then press off the tire on both sides, coating the rim flange with assembly compound.

- Lift the first side of the tire over the assembly head (Fig. 1017 - 44). Place a rag or a leather cloth between the wheel and the tire lever.

In addition, make sure the tire remains in the drop center opposite the disassembly head (Fig. 1018 - 44). Use Special Tool 9539 to facilitate this.


- Remove the second side of the tire in the usual manner.

911 Carrera 4

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