Formula One transmissions are the most advanced in the racing world, with an unparallel combination of performance, weight and packaged size. A key part of the gearbox is the casing, as it forms not only a housing for the gearbox internals but also acts as an integral part of the car’s structure. Here I will look at some of the construction methods and materials used to create these casing. Read more…

It is hard to imagine that a current-generation racecar, in a leading race series, owes its gearbox design to a unit that first appeared in a roadcar in 1957. However, this is the case in NASCAR Cup, where the only approved gearbox designs still have to resemble the venerable Borg Warner ST10, first used by General Motors in the 1950s. The external appearance is where the similarity ends though, with the internals, provided by a number of manufacturers, bringing the design right up to date. This article will look at some of the areas where Read more…

The latest transmission development in the top flight of motorcycle racing, MotoGP, has been the appearance of seamless shift technology. Already commonplace in Formula One, seamless shifting provides a number of benefits to the rider and, more important, helps reduce lap times.

Honda is currently the only team on the grid to admit to using a system, and it certainly made an impact on its Read more…

Le Mans places abnormal demands on almost every component in a racecar, with the suspension and engine taking a relentless pounding on every lap of the 13.629 km circuit. Also subject to the same war of attrition is the gearbox and driveline. In the past, gearboxes were a regular source of problems for competitors, either thanks to simple fatigue failures of parts, or driver fatigue leading to missed gearshifts. In recent years, transmission problems have become far less commonplace; this has been thanks to a number of Read more…

With the exception of off-road racers competing in events such as the Dakar Rally, it is unlikely that any type of competition vehicle is required to deal with as varied a range of conditions as a WRC rally car. Ten years or so ago, WRC cars were far removed from any other type of current rally machinery, but with introduction of new rules in 2006 and Super 2000-based regulations in 2011, the complexity of the designs manufacturers can employ has been greatly reduced. Read more…

It is common to see composite materials in a range of applications in motorsport. Typically glass- and carbon fibre composites reinforced within a polyester or epoxy matrix not only lend themselves to the manufacture of complex shapes but also allow engineers to incorporate both isotropic and anisotropic mechanical properties into a single structure. As with all composite materials, the constituents’ properties and the positioning of both the reinforcement and matrix material will determine the overall composite material’s properties.

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In order to reduce stress and improve mechanical performance for any highly loaded powertrain component, surface finish is of the utmost performance; a superior surface improves fatigue resistance by removing potential stress raisers and the possibility of crack propagation. For geartrain components this is especially important, requiring high surface hardness to maintain impact strength and resist bending loads on the gear teeth, even though most of the gear material itself must exhibit enough ductility to reduce the risk of brittle failure under shock loading. Furthermore, any Read more…

In a previous RET-Monitor article we looked at how these ‘Back Torque Limiters’ or ‘Slipper Clutch’ units operate, and their particular advantages in motorcycle applications. They allow a controlled slipping of the clutch until the speeds of both the rear wheel and the engine are matched, and have found their way into many motorcycle race formulae including World and British Superbike, Supermoto and even Motocross. While not exclusively suited to motorcycle applications, installing these units into bike-engined kit cars has become more commonplace. Read more…

Although attaining speeds up to and in excess of 100 mph on tarmac is not an arduous task, it is a rather more multi-faceted undertaking on water. One of the many considerations of high-speed marine applications is transmission and propeller design. There are a number of high-speed marine formulae that use various propulsion systems, including water-jet drives, super-cavitating and surface-piercing propeller drives.

The Oulton Broads and surrounding areas, in Suffolk,

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In the previous article on this subject, I looked at a reversing differential for a bike-engined car where the engine is mounted longitudinally. Many bike-engined cars are configured with the engine mounted transversely, as it is in the motorcycle from which it is taken. This arrangement is commonly seen in Formula Student, for example.

One particularly enterprising car constructor has developed, and very successfully used, its own Read more…