The two-stroke motocross bike is all but dead. The epic staple of the motocross industry from decades ago is now an aging relic. The trademark br-a-a-a-a-a-a-a-p of a properly tuned 125cc two-stroke motocross bike is now a rarity, and the four-strokes have already begun their assault on the mini bike classes.
The fact that two-strokes are quickly becoming an antique in the motocross world is undeniable. But what exactly killed this ingenious technology? Two-strokes are lighter, faster (at the same displacement), cheaper to buy and maintain, and easier to work on. On paper they are a clear victor over the louder, heavier, more expensive and more complicated four-strokes. So, what exactly is responsible for the demise of the two-stroke?
Racing Organizations (AMA/FIM)
When the four-stroke was first introduced, it was a joke. Heavy, expensive, loud and slow. Riding one was more of a way to make a statement about your personality than to actually ride the best bike available. So, racing organizations such as the AMA and FIM felt it necessary to give them a (huge) handicap. Almost double displacement for Motocross/Supercross class and exactly twice the displacement for the Lites classes. At the time this felt like a sensible move. The newer technology needed the extra motor size in order to even be remotely competitive.
The problem with the assumption by the AMA and FIM that the four-strokes are slower by nature is that it is wrong. Sure, you can make an argument that the piston travels four time as far for one revolution, but in practice, four-strokes can produce almost the same amount of power as an equally displaced two-stroke. As technology has evolved, the twice as large four-stroke engines have rocketed ahead of two-strokes, making two-strokes too slow for serious competition in the pro or national amateur levels.
While it is not really the pros fault that they have all moved to four-strokes, they are largely responsible for the demise of two-strokes in public opinion. Whether they switched due to corporate pressure or just because four-strokes are faster, the end result is the same: all pro riders now ride four-strokes.
This rather quick and unanimous change of preference had a lasting effect on public opinion. While 250 two-strokes were once cutting edge, they started to look outdated. Ricky wasn’t riding one, Kevin wasn’t riding one, why should I be riding one? Local pros and amateurs who wanted the latest and greatest were drawn by the technologically advanced four-strokes and thus made the switch along with Ricky, Kevin, Chad, and eventually James.
While it is impossible to blame the pro riders for their switch, they had to do it to stay competitive, the truth is that the decision by many and eventually all of the professional motocross riders to ride four-strokes had long lasting effects on the public opinion on four-stroke vs. two-stroke.
At first, the four-stroke was great for the manufacturers. They could treat it as a little pet project, and still make a sizable profit of it. It allowed them to explore the upcoming technologies while still making progress on their flag-ship two-strokes. However, as the four-stroke gained popularity, manufacturers such as Honda, Yamaha, Suzuki, Kawasaki and KTM were faced with a tough decision. Economically, they could not feasible keep producing and innovating on both the four-stroke and two-stroke platforms. Furthermore, it did not make sense for them to keep producing two essentially competing products. They had to make a choice, and they choose four-strokes.
Ever since the manufacturers have chosen the four-stroke as their priority in R&D, the two-strokes have only fallen further behind. Most remain unchanged year to year, and thus there is even more motivation for riders to switch to four-strokes. Even chassis and control changes which could be fitted to two-strokes largely do not, simply because the manufacturers have moved away from the platform as a whole.
At first, the four-stroke was a vet riders dream. They were so much easier to ride, the extra weight didn’t really affect their riding style much, and the price was not an issue as most vet riders are well off financially. Obviously, the vet market is where the four-strokes first took off. They blew up among 40 and 50 year old motocross riders, and the whole movement essentially rode on their backs. Once the younger and more competitive riders saw how the four-strokes complimented the laid back riding style of the vet riders, they instantly wanted to jump on the four-stroke bandwagon. Once this movement began, it couldn’t be stopped, and hasn’t even now.
Will They Be Resurrected?
Our economy is in rough shape. There is no denying that the motocross industry will take a big hit in the upcoming months as gas prices ride, stock prices fall and jobs are lost. The motocross industry will not be exempt from these hardships.
As a result, dedicated motocross racers everywhere will have to make sacrifices in order to keep racing. One of these sacrifices, I believe will come in changing back to two-strokes. Two-strokes are cheaper to buy, maintain, and modify. Because of this, frugal riders will be more than willing to sacrifice some power and rideability in order to keep racing economically.
What Does the Future Hold
The future of the entire motocross industry is currently unknown. If we are able even to survive the upcoming economic crisis, what will our world be like on the other side? Will motocross still be even remotely popular? We may not know for 10 maybe 20 years what our future will hold.
Furthermore, does the four-stroke/two-stroke debate even matter if our future is clearly in green energy technologies?
While I do believe that greener motocross bikes, maybe even electric or solar powered will one day “rule the roost,” I also believe that in the short term, the dominant technology will depend on the economy. If the economy worsens, I strongly believe that two-strokes will end up on top due to their cheaper price in general. On the other hand, if gas prices continue to fall and our economy turns itself around, then four-strokes may stay on top.
The bottom line is that the reign of the four-stroke is destined to be short lived. Their rise was artificially supported by political and economic motives and thus they will soon be replaced by either green technologies, or fall to the cheaper two-strokes.