Wheelset development at AC Schnitzer A few definitions in advance Wheel/complete wheel = rim incl. tyre Wheel set = 4 wheels xi/xd wheel sets = special wheel sets for all-wheel drive vehicles (xDrive) Mixed-sized tyres = tyres wider on the rear axle than on the front axle All-round tyres = same tyre size on the front and the rear axle The wheels have a really important role: they are the postcard-sized connection between the vehicle and the road. They play a key role in the driving and propulsion as well as the deceleration - i.e. braking - of your vehicle. This gives the wheels a key role. Anyone who develops and sells wheels therefore has a great responsibility. We are aware of this responsibility; we have internalized it and implement it with every new development. AC Schnitzer only uses high-quality brand tyres, which are developed in close cooperation with premium tyre manufacturers. On the one hand, the tyres have to transfer the power of the engine perfectly to the road, on the other hand, properties such as braking behaviour, lateral control, water drainage in rain and the properties in straight running are important decision criteria for or against a tyre. A wheel set with wide base tyres is always also an investment in increasing driving safety and dynamics. In order to maintain driving comfort when using larger wheel dimensions, we at AC Schnitzer have actively opted against run-flat tyres and for sporty, conventional tyres. Conventional tires build up less rolling resistance and offer noticeably more comfort. AC Schnitzer specialises in mixed-sized tyres, i.e. wheel sets in which the wheels of the rear axle are wider than those of the front axle. This makes sense in terms of driving dynamics, as it allows strong drive forces to be transmitted while at the same time enabling high steering precision. Although the wider a tyre is, the more power you can put on the road, the rolling resistance caused by the tyre must not become too high. As the rolling resistance increases the wider a tyre is, AC Schnitzer works out the wheel dimensions that are balanced. AC Schnitzer develops special wheel/tyre combinations for all-wheel drive vehicles and orientates itself on the specifications of the vehicle manufacturer. These AC Schnitzer wheel sets are marked "xi/xd". Only those wheel dimensions are developed and approved for all-wheel drive vehicles that are as gentle on transfer cases as standard wheel sets. All AC Schnitzer wheel sets are tuned in multi-stage driving tests in traffic and on race tracks. Only after successful test runs the wheels are released for sale. All AC Schnitzer wheel sets are delivered fully assembled and balanced. They are subject to a two-year manufacturer's warranty. The scope of delivery includes mounting materials such as adapters and wheel bolts as well as the homologation certificate (with the exception of marked wheelsets for export). Philosophy/Design Generation change for AC Schnitzer rims Not only the name is new, but also the design - both point to a generational shift in the wheel segment at AC Schnitzer. Although the AC1 rims are a new design, in one important aspect they pay tribute to their heritage: they too will certainly become a design classic. With the new AC1 rims, AC Schnitzer has reinterpreted the classic twin-spoke design. The result is a sporting hybrid look. In a sophisticated style, triangle tips taper towards the rim edge and widen towards the centre, separated by five trapezoids. These draw the eye directly to the unique classic element of the AC1 rim: the pentagonal hub cap with AC Schnitzer logo. Despite this multiplicity of styling elements, the design appears clean and masculine thanks to the very straight lines. The interplay of all these elements gives the AC1 wheel solidity and size. Especially in motion, the BiColor finish creates a strongly alternating effect. - weight-optimised cast alloy rims - produced in the low-pressure casting process with subsequent heat treatment - open 5-spoke design in BiColor which gives a clear view to the brakes - embossed original AC Schnitzer logo - the wheel is corrosion-protected with a high quality clear lacquer, - guaranteeing a long life - the basic rim of the AC1 wheel family Material Only high-quality aluminium alloys with the AlSi7 or AlSi11 specification are used. Both types of material are additionally heat-treated in the production process, which results in higher strength and simultaneous weight reduction. Material samples during the production process guarantee the constant and high quality of the material. Production Steps on the way to perfection A high-quality cast blank is the prerequisite for a perfect and durable wheel. AC Schnitzer uses the low-pressure casting process for its manufacture. The aluminium alloy is pressed into a multi-part casting mould at a pressure of up to 1.2 bar. After cooling to approx. 400 degrees Celsius, the mould is opened and the cast blank is ready for further processing. This takes place during machining and a complex painting process. X-ray inspections, leak tests and the use of various measuring methods throughout the entire manufacturing process guarantee the consistent and high quality of the wheel. Surface BiColor In this process, the wheel is first primed, then completely painted and finally sealed with an acrylic clear lacquer. Now the surfaces, which are later to shine metallically bright, are turned off. Finally, a two-layer clear coat is applied, consisting of a polyester primer and the acrylic clear coat. Test Procedures / Safety After their design, the first sample rims are manufactured under real production conditions. These must undergo a multitude of tests. Among other things, the strength is tested. The "rim life" is simulated in the bending circumferential test. Every AC Schnitzer rim must withstand this intact in order to be allowed to be produced and sold at all. This is followed by vehicle-specific tests, including test installations with check of unobstructed movement and driving tests on public roads and on race tracks. Only after these procedures our rims receive their homologation, i.e. the approval to be used in road traffic. Wheels are safety-relevant components. Therefore, they are checked and tested with the greatest care. This starts with the first chemical material tests and ends with hard testing machine endurance runs: - § 30 StVZO wheel guideline - ECE R124 - Bending-rotation tests - 90° impact test - unwinding tests Uniqueness of the wheel set with the AC1 Light Alloy Wheels - Engineered in Germany - Heat treated - With exclusive AC Schnitzer lettering - Compatible with standard RDC system - Rim also available separately - Warranty 2 years - Production monitored according to ISO standard - BiColor black optionally also in anthracite - KDS mount for wheel alignment according to BMW specification is available