Magnesium wheels

Magnesium wheels are wheels manufactured from alloys which contain mostly magnesium. Magnesium wheels are produced either by casting (metalworking) (where molten metal is introduced into a mold, solidifying within the mold), or by forging (where a prefabricated bar is deformed mechanically). Magnesium has several key properties that make it an attractive base metal for wheels: lightness; a high damping capacity; and a high specific strength. Magnesium is the lightest metallic structural material available.[1] It is 1.5 times less dense than aluminium, so magnesium wheels can be designed to be significantly lighter than aluminium alloy wheels, while exhibiting comparable strength. All competitive racing rims are now made of magnesium alloy.[2]

Cast magnesium wheels

Taking into account their generally inferior quality compared to forged wheels, the main advantage of cast wheels is the relatively low cost of production. And although cast wheels are more affordable than forged wheels, cast wheels are heavier than forged wheels for a given required load. Manufacturing defects found in cast wheels include cavities or porosity and a different metallurgical microstructure, entailing larger grain size.[3] Cast wheels will tend to fracture upon overbearing high-speed impact, whereas forged wheels will tend to bend.

Forged magnesium wheels

Forged magnesium wheels are manufactured by mechanically deforming (forging) a prefabricated rod using a powerful forging press. Several somewhat different forging techniques exist, all of them comprising a multi-step process/operation. The resultant forging is subsequently machined (lathe-turned and milled) into the final shape of a wheel by removing excess metal from the forged blank. A forged magnesium wheel is 25 percent lighter than cast wheel. The main disadvantage of forged wheels is the high manufacturing cost. And due to the typically high costs of finished wheels, forged wheels are still rarely purchased by non-professional drivers for regular road use.

But since forged wheels can be designed to be lighter than cast wheels for a given load, forged wheels do offer fuel economy and other distinct advantages. The forging process allows alignment of the metal fibers and optimization of the directional pattern arrangement along the spokes of a wheel. This, along with the smaller grain size, results in superior mechanical properties and performance characteristics that make forged magnesium wheels widely popular both for motor racing and with knowledgeable driving enthusiasts.


The original cast magnesium wheels were made beginning in the 1930s and their production continues today. Some of the biggest brands producing magnesium wheels in the past include Halibrand, American Racing, Campagnolo, Cromodora, Ronal, Technomagnesio, and Watanabe. The popularity of magnesium wheels peaked in 1950 -1960. Magnesium wheels from the middle of 20th century are now considered classic and are highly sought by some classic car enthusiasts. However, those magnesium wheels proved to be impractical because they were prone to corrosion and they were mostly used in racing sports. After 1960’s magnesium wheels were gradually replaced by aluminium alloy wheels on the mass market, but not from the competition wheels market. Many manufacturers of magnesium wheels are still operating. A lot of companies continued production after 1960’s although in lower quantities. Modern scientific and engineering developments led to significant improvements in magnesium wheels qualities, including high-tech anti-corrosion treatment that extends the lifecycle of a wheel to match or even exceed the lifecycle of comparable aluminium alloy wheel.

Common issues

A notable disadvantage historically affecting magnesium wheels was susceptibility to corrosion. Recent improvements in magnesium surface treatment technology have largely resolved the corrosion issues—to the extent that some manufacturers today offer a 10-year warranty.

A common misconception persists regarding the danger caused by magnesium’s flammability. But new improved alloys have been developed over the past fifty years, with no reportable incidents of magnesium wheels catching fire. In fact, the U.S. Federal Aviation Administration has conducted wide-ranging tests over the past decade, concluding that the potential flammability of magnesium is no longer a concern—and even ruling to allow its use in aircraft cabins.[4]

With many challenges solved by modern technological solutions, a number of companies—including Brembo (Marchesini), BBS, OZ, Taneisya, and SMW—are now producing the next generation of reliable forged magnesium wheels. Additionally, several car and motorcycle manufacturers (Original Equipment Manufacturers, or OEMs) have successfully homologated forged magnesium wheels for use as original equipment. Only a limited number of forgers in the world have the large presses required to manufacture the forgings, from which forged magnesium wheels are machined.

Aftermarket magnesium wheels

Minilite magnesium wheels

Minilite wheels are 8-spoke design wheels, developed in 1962 for Austin Mini. Magnesium alloy was chosen for weight savings, and Minilite wheels quickly became a popular choice for racing and road use. Designed initially for a specific vehicle, the original 8-spoke pattern was subsequently extended to various sizing dimensions to accommodate a range of vehicles. Used by race teams in Europe and the United States, Minilite was one of the most popular competition wheels of the 1960s and 1970s. Small-scale production of magnesium alloy Minilite wheels continues today.[5]

Speedline wheels

Speedline is an established brand of light alloy wheels for OEMs, racing (single-seater and rally), and aftermarket. Some racing wheel models are made from cast magnesium alloy.


Marvic is an Italian manufacturer of alloy wheels for motorcycles, including racing team cycles. With its own in-house magnesium foundry, Marvic makes cast and forged magnesium wheels (as well as forged aluminium). The company also offers wheels for vintage motorcycles and cars, including replicas of historic models, and replica Campagnolo and other wheels in original magnesium alloy.[6]

Washi Beam

Washi Beam Co. is a Japanese manufacturer specializing in forged automotive wheels. Founded in 1971, the company began forging aluminium road wheels in 1984 and magnesium racing wheels in 1992. The company claims to have forged more than 24,000 wheels for Formula 1 teams. The wheels for Formula 1 cars produced by Washi Beam are distributed under BBS trademark. Washi Beam also supplies numerous automotive original equipment manufacturers.[7]


Tan-ei-sya Co. is a Japanese manufacturer of automotive alloy wheels, reportedly having an in-house forging facility. Production of magnesium forged wheels began in 1990, and the company began supplying forgings for manufacturing Formula 1 magnesium wheels in 1993. TWS Forged brand was launched in 2010 to establish the manufacturer’s presence in the aftermarket. Single-part and multi-part forged magnesium wheels are available.[8]


SMW Engineering is leading manufacturer of forged magnesium wheels and wheel forgings (semi-finished). SMW supplies its wheels under private label, along with aluminium forgings to various automobile and motorcycle wheels manufacturers and many motorsports teams, including MotoGP and Formula 1. SMW reportedly has an advanced forging process on larger presses, providing for higher mechanical and performance characteristics. The company uses a special coating process and offers a long warranty on its products. SMW is also involved in forging jet parts and aircraft components.[9]


  1. “More than mag wheels”.
  3. Mintskovsky, Paul. “F1 Wheels”.
  5. wheels, Minilite,Minilite wheels,historic and classic car wheel replacement, mini lite. “Minilite,Minilite wheels,historic and classic car wheel replacement,competition and Classic Car Enthusiast,mini lite wheels”.
  6. “Produzione di getti e ruote in magnesio”.
  7. “Welcome to Washi Beam”.
  8. “Tan-ei-sya”.
  9. “SMW forged wheels”.
Rim (wheel) The rim is the "outer edge of a wheel, holding the tire". It makes up the outer circular design of the wheel on which the inside edge of the tire is mounted on vehicles such as automobiles. For example, on a bicycle wheel the rim is a large hoop attached to the outer ends of the spokes of the wheel that holds the tire and tube. The term rim is also used non-technically to refer to the entire wheel, or even to a tire. In the 1st millennium BC, an iron rim was introduced around the wooden wheels of chariots. Cross section of a bicycle rim wooden bicycle rim with tubular tyre Characteristics Scratched rim on two-piece wheel. Black residue remaining from where the tire was seated on the "safety profile" rim. Diameter (effective): distance between the bead seats (for the tire), as measured in the plane of the rim and through the axis of the hub which is or will be attached, or which is integral with the rim. Width (e...
Tweel The Tweel (a portmanteau of tire and wheel) is an airless tire design concept developed by the French tire company Michelin. Its significant advantage over pneumatic tires is that the Tweel does not use a bladder full of compressed air, and therefore it cannot burst, leak pressure, or become flat. Instead, the Tweel assembly's inner hub connects to flexible polyurethane spokes which are used to support an outer rim and these engineered compliant components assume the shock-absorbing role provided by the compressed air in a traditional tire. The Tweel airless tire design Design The Tweel consists of a band of conventional tire rubber with molded tread, a shear beam just below the tread that creates a compliant contact patch, a series of energy-absorbing polyurethane spokes, and an integral inner rim structure. Both the shear beam and the polyurethane spokes can be designed to provide a calibrated directional stiffness in order that design engineers are able to control both how th...
Wheel A wheel is a circular component that is intended to rotate on an axle bearing. The wheel is one of the key components of the wheel and axle which is one of the six simple machines. Wheels, in conjunction with axles, allow heavy objects to be moved easily facilitating movement or transportation while supporting a load, or performing labor in machines. Wheels are also used for other purposes, such as a ship's wheel, steering wheel, potter's wheel and flywheel. Common examples are found in transport applications. A wheel greatly reduces friction by facilitating motion by rolling together with the use of axles. In order for wheels to rotate, a moment needs to be applied to the wheel about its axis, either by way of gravity or by the application of another external force or torque. Using the wheel, Sumerians invented a contraption that spins clay as a potter shapes it into the desired object. Three wheels on an antique tricycle The earliest wheels were m...
Artillery wheel The artillery wheel was developed for use on gun carriages when it was found that the lateral forces involved in horse artillery manoeuvres caused normally constructed cart wheels to collapse. Rather than having its spokes mortised into a wooden nave (hub), it has them fitted together (mitred) then bolted into a metal nave. Its tyre is shrunk onto the rim in the usual way but it is also bolted on for security. A normal wagon wheel is dished so that in its lowest part, the spokes are perpendicular to the ground thus supporting the weight (with the axle not truly horizontal but angled downward toward the outside about 5 degrees). This is not done with artillery wheels.    Artillery wheel Motor vehicles 1927 Ford T with artillery wheels When higher speeds and consequently higher lateral forces were attained with the introduction of motor vehicles, the artillery wheel was used in those too. By the 1920s, motor cars used wheels that looked at a glance...
Alloy wheel In the automotive industry, alloy wheels are wheels that are made from an alloy of aluminium or magnesium. Alloys are mixtures of a metal and other elements. They generally provide greater strength over pure metals, which are usually much softer and more ductile. Alloys of aluminium or magnesium are typically lighter for the same strength, provide better heat conduction, and often produce improved cosmetic appearance over steel wheels. Although steel, the most common material used in wheel production, is an alloy of iron and carbon, the term "alloy wheel" is usually reserved for wheels made from nonferrous alloys. The earliest light-alloy wheels were made of magnesium alloys. Although they lost favor on common vehicles, they remained popular through the 1960s, albeit in very limited numbers. In the mid-to-late 1960s, aluminum-casting refinements allowed the manufacture of safer wheels that were not as brittle. Until this time, most aluminum wheels suffered from low ductility, usuall...