2012. Isn’t that the end of the Mayan calendar? Which, in some people’s minds, suggests the end of the world? Evidently the FIM (Federation International de Motocyclismo) didn’t get the apocalyptic memo. MotoGP racing will continue as planned while actually expanding capacity.
The one big change for 2012-just confirmed in an official FIM statement to teams-the Premiere Class will see the return of 1000cc displacement machines (the current limit, enacted in 2007, is 800cc). Well, truth be told, if you want to pick hairs, the displacement in former years (2002-2006) was actually 990cc.
Since 1949, when the FIM first created the World Championship Grand Prix motorcycle racing series, there has been a steady evolution in technology, fostering numerous incarnations of engine design. Throughout the 50s and 60s all the GP classes, from 50cc to 500cc were pretty much dominated by 4-stroke plants.
2-strokes, which had started to gain prominence in the smaller divisions in the 60s, became ubiquitous in all classes by the 70s and ushered in one of the most dynamic periods in racing.
Lightweight, 500cc 2-stroke machines (usually in a 4-cylinder platform) were the preferred mounts and owned the top class from the mid-70s until 2002 (although Honda made an ill-fated attempt to go up against the dominate 2-strokes in 1979 with their NR500). The blistering sight and sounds of the irascible 500cc 2-strokes circulating circuits was unmatched.
For those who have never ridden a 2-stroke, the basic physics of how the transfer ports work in delivering fuel to the combustion process via the movement of the piston, results in an extremely narrow powerband. With power delivered in a virtual "on-off" hit, the bikes were nasty little hornets with explosive temperaments. But incredible to watch.
In 2002 rules were implemented in MotoGP to reintroduce the use of 4-stroke engines. Some argue that the 2-strokes were losing popularity as a result that there was no correlation to the products being offered by manufacturers to the public.
However, a strong argument could be made that, like in motocross, the racing series was merely accommodating the environmental issues that had sounded the death knell for 2-strokes, which had begun over the preceding few decades. 2-Strokes, despite the finest tuning, inherently are somewhat inefficient, allowing as much as 30% of their unburned gases to escape into the atmosphere.
It was academic that 2-strokes would eventually fall from favor and therefore, need to be phased out of the international racing scene. The rule changes of 2002 allowed 2-stroke machines (provided they didn’t exceed 500cc) and 4-stroke machines (not to exceed 990cc) and permitted choice of configuration. Within one season the 4-strokes had evolved to such impressive performance levels that the 2-strokes vanished from the grid.
In 2007, the FIM, in an effort to curb the advancing speeds of MotoGP’s rapidly evolving premiere class, reduced the maximum displacement to 800cc, as well as introducing a host of rules governing number of cylinders, which in turn determined weight limits.
The majority of teams have settled on a 4-cylinder engine (in either a V or in-line configuration) for the best balance of weight, power and fuel consumption.
As far as the intention of curbing speeds, engineers-true to form-merely figured out ways to coax more performance out of the smaller engines (despite the added restrictions of limiting the number of engines a team can use over the course of the year) and lap times have dropped while top speeds have increased.
So, after all the passing of time, all the incarnations of various engine configurations, the introduction, development, and eventual demise of the 2-stroke, rule changes, and the impact of environment awareness, MotoGP’s Premiere Class will once again feature 1000cc 4-strokes, lifting the 800cc limit that was put into place in 2007, and will welcome the mighty machines back onto the grid.