FAQ - Frequently asked questions

  • What is a pitch circle diameter?

    The pitch circle diameter is the diameter in mm of the circle on which the centers of the bolt holes of the wheel lie.

  • What is the offset?

    The offset (ET) is the distance between the center line of the wheel rim and the inner fixing face. The offset is stated in mm.

  • What is a KBA number?

    The KBA (Federal Office for Motor Vehicles) number is issued to wheels approved for use in Germany. It should not be confused with the wheel number.

  • Where do I find the wheel number?

    The wheel number (generally 6 to 10 digits long, and does not begin with 0 or the letters KBA) is cast into the wheel. It can be found on the inner face of the wheel or also under the wheel trim.

  • What is a part approval?

    A part approval is a report by a technical assessor or test center regarding the compliance of a vehicle to regulations when the parts in question have been fitted correctly. A part approval always requires approval of the fitting work.

  • What is a TÜV approval and why is this necessary?

    This part approval gives information regarding the compliance of a vehicle to regulations when a part has been fitted. It contains the specifications for fitting, together with any conditions and restrictions. After a part has been fitted, acceptance of the change must be performed.

  • What is an ABE (General Operating Permit)?

    The ABE is a German national permit for a vehicle or parts of a vehicle. It is issued by the Federal Office for Motor Vehicles (KBA) to a manufacturer. Wheels with ABE permits are not generally subject to fitting approval, i.e. for a particular wheel-tire combination there are no conditions that must be observed and thus no requirement to make an entry on the vehicle registration papers.

  • How are wheels fitted?

    Care must be taken that the seating faces on the vehicle are clean and free of burrs. When fitting wheels please use only the fasteners supplied, or the original fasteners supplied by the vehicle manufacturer. More details on the use of original fasteners can be found in the respective TÜV approval or the ABE. When tightening nuts and bolts, comply with the tightening torque specified by the vehicle manufacturer.

  • What is a tightening torque?

    Generally the tightening torques applicable are those specified by the vehicle manufacturer, which can be found in the operating manual for the vehicle. More details can be found in the approval report or the ABE.

  • How many thread engagement turns must the wheel bolt make?

    The attachment bolts must make at least 6.5 thread engagement turns.

  • How should a wheel be properly cleaned, and which cleaning products are suitable?

    Regular cleaning helps keep the wheels in good condition and maintains your pleasure with your alloy wheels. We recommend the use of hot water with a commercially neutral car shampoo added. We advise against the use of rim cleaners which contain acid. The use of steam jets, metal cleaning compounds and steel wool should be avoided; a micro-fiber cloth is suitable.

  • What is the best way to store alloy wheels?

    Ideally, alloy wheels should be hung up and stored in a well ventilated dry room.

  • Can I (re) polish alloy wheels?

    (Re)polishing generally means removal of the paint finish, followed by surface treatment to achieve a high-gloss polish. The durability characteristics of the industry are achievable only with carefully matched systems, which generally cannot be achieved using do-it-yourself processes. Therefore without adequate protection the polished surface becomes prematurely unsightly, which can lead to weakness and affect the fatigue strength of the wheel.

  • Generally, can damage (such as accident damage) to alloy wheels be tolerated?

    Because of the many types of possible damage (such as accident damage) to alloy wheels, no general statement can be made regarding toleration of damage. In each individual case there must be an investigation to discover whether the accident has resulted in the wheels suffering plastic deformation or cracking.

  • Where can I buy RONAL and SPEEDLINE CORSE wheels?

    You can buy RONAL and SPEEDLINE CORSE wheels at your trade dealer.

  • Where can I obtain spare parts for RONAL and SPEEDLINE CORSE wheels?

    Spare parts such as wheel bolts, wheel nuts, centering rings and hubcaps can be obtained from your trade dealer.Händler