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Two Stroke vs. Four Stroke – Let the debate begin

by JohnNicholas on 01/14/2009

Whenever the debate between two strokes and four strokes begins, proponents on both sides bring up various reasons to defend their position.

In many cases, real facts with proof are ignored, misused or misunderstood. At times, the arguments boil down to hearsay. Some of it  blatant lies.

This is has created a divide between the 2T’s, the 4T’s and their supporters. Each side becomes defensive and many times useful discussions turn bad quickly.

This is bad for our beloved sport of motocross.

Every one has an opinion and they are entitled to their opinion. But at times that opinion may not be based on facts.

Let’s look at some of the most commonly stated reasons four stroke racers and two stroke racers debate. I will not go into detail on any of them right now, but just get them out on the table. We will examine each in depth over the following weeks and months.

Yamaha YZF engine cutaway.

• Four Stroke technology has surpassed Two Stroke technology. Many four stroke supporters say that the two stroke has had it’s day and it’s now the four stroke generation.

• The EPA (Environmental Protection Agency, USA) has a ban planned for all Two Strokes, so the manufacturers had to switch to four strokes, beginning in 2010.  Since California has the strictest environmental laws and all four manufacturers have their US headquarters located there, this ruling would have a huge impact.

• The four stroke revolution has brought about higher sound levels that threaten to destroy motocross. While the sound of a two stroke may be louder when you are right next to it, as compared to a four stroke, that sound does not carry near as far. The booming four strokes can be heard for literally miles away. This has lead to riding areas being shut down and anger among neighbors of riding areas.

• The FIM / AMA rule change allowing a displacement disparity between 2T and 4T race machines. This was unprecedented in all of racing. It was not just that they allowed an advantage, they allowed the four stroke to be double the displacement of a two stroke.

TM Racing 125cc engine.

• The four stroke bike is easier to ride fast and they inspire confidence. Jumps that would have been impossible to perform on a two stroke are easy on a four stroke. But is this a mixed blessing? Could this be the catalyst that has lead to racers getting injured, because they had taken a shortcut in their racing education?

• The cost of racing has increased dramatically.  Just the exhaust system for a 4T costs at least double if not triple the cost of a 2T system.

• The upkeep, rebuilding and maintenance costs are much higher for the 4T than the 2T.

• When is a DNF not really a DNF? In professional racing, there is now a phenomenon when racers fall or stall and they are unable to restart their four strokes. The result – lost races and National Championships because a highly paid professional racer can not restart his race machine.

These issues are just some of the challenges that our sport is facing. We are not only in danger of  losing the two stroke, but the future of motocross could be in jeopardy.

Over the next few weeks/months I will explore each of these issues in depth, supported by facts from relevant sources. It is time to leave the emotion-based opinions behind and work together to build our sport up to new heights.

As always, I am interested to hear what you have to say on this subject. Please feel free to leave a comment below.

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