This was posted on the old site some time ago, but I thought it was worth reading for those that missed it....
"Is the two stroke dead? Not completely. But it's getting hard to find it's pulse. This is a shame, a crying shame, because what this sport needs is a good inexpensive racing motorcycle.
And no engine is better suited for motocross than the two stroke. Contrary to popular belief, pound for pound, cubic centimeter for cubic centimeter and head to head, the modern four stroke is an antiquated piece of agricultural equipment when compared to a two stroke.
Yes, Virginia, we know that isn't the way it is portrayed in the mass media, but it is true. And we can prove it.
As Dragnet's Sergeant Friday would have said during the first four-stroke era, "Just the facts ma'am."
Horsepower: A two-stroke engine produces 0.2 horsepower per cubic centimeter (a YZ250 makes 50 horsepower out of its 250cc of displacement). A four-stroke only makes 0.12 horsepower per cubic centimeter.
Moving parts: Stripped to it's essence, a two-stroke engine has three moving parts (crank, rod and piston). A four-stroke has five times as many moving parts (and over 100 extra auxiliary parts)
Weight: A two-stroke engine weighs 15lbs less than a four-stroke engine.
Cost: The rebuild cost of a 250cc two-stroke ($250) is five times less than that of a four-stroke ($1250). And in the case of a major malfunction the rebuild cost of a two-stroke can be as much as 12 times less.
Performance: If you compare a 250cc two-stroke to a 250cc four-stroke, the two-stroke is a vastly superior machine, making 33 percent more power (50 horsepower versus 35) with quicker rev, snappier powerband, simpler design and lower cost.
Given these facts you might be asking yourself, "If all of this is true, then why is everyone buying four-strokes?" And the answer isn't what you think.
First, the four-stroke revolution was not a Japanese manufacturer conspiracy to sell more motorcycles. On the whole the motorcycle manufacturers had little to do with the advent of the racing four-stroke.
It was the brainchild of a lone Yamaha engineer. Yoshiharu Nakayama had to fight corporate reluctance to get his single prototype built. Apart from Yamaha, everyone considered Nakayama's YZ400F to be folly (which is why it took them four to six years to respond with their own four-strokes).
Second, the EPA had nothing to do with four-stroke motocross bikes. They do not regulate closed-course competition machines.
Third, if your looking for someone to blame for the four-stroke migration, blame Roger DeCoster, Keith McCarty, Brue Stjernstrom and Chuck Miller. As team managers and representatives on the AMA Advisory Board, they signed off on allowing Yamaha to race its hand-built, one-off, exotic YZ400 proto.
Even worse, they were so sure that it would be a failure that they gave it an upper displacement of 550cc to race in the 250 class. Talk about short sighted! It wasn't until the damage was done that the AMA lowered the displacement to 450cc-which proved in hindsight to be way too much.
Finally, all fingers must point at the AMA. The only reason that James Stewart, Ricky Carmichael, Ryan Villopoto, Chad Reed and Davi Millsaps are racing four-strokes is because four-strokes are allowed to be 100% larger than a 125cc two-stroke and 80% larger than a 250 two-stroke. Take that displacement advantage away and four-strokes would be relegated back to play bike status.
For the last three years the MXA wrecking crew has been imploring the AMA powers-that-be to do something to save the two-stroke in racing. Our simple solution was to legalize big-bore 125 and 250 two-strokes to compete against the already big-bore four-strokes.
Nothing could be simpler... or fairer. We didn't suggest this because we love the smell of castor oil in the morning, but because the overall health of our sport depends on people being able to afford to pursue it.
To say that the AMA turned a deaf ear to our suggestion that they do for the two-stroke exactly what they did for the four-stroke would be an understatement."
