Six Strokes and Four Wheels
Yamaha makes two bikes which get rave reviews from riders, so when they're put head to head, which comes out on top?
Which engine type makes a better motocross motor?
There's a rumbling in the air around motocross tracks, but it's not the kind of thunder created by nature. It's the baritone rasp of a high-po 4-stroke engine kicking roost at the pre-mix gang on their 2-strokes.
It's a revolution of sorts, where the dirty, mosquito-toned 2-strokes are clinging to the last vestige of their relevance in the face of governmental regulations and new 4-stroke designs. If you missed it, here is our detailed description of the rise and fall of 2-strokes.
Yamaha, being the first of the big factories to field a competitive 4-stroke motocrosser, has become the leader in 4-stroke dirt bikes. Thus far, it's the only company to have won a national championship on the booming 4-strokers.
The success on the track for Yamaha's 4-stroke dirt bikes has resulted in a huge jump in sales of its range of competition dirt bikes, up 127% from 1997 through 2001 compared to the industry's 87%. Though its 2-strokes remain near the top of the sales charts, it's the 4-stroke YZ and WR 400/426Fs and 250Fs that have really boosted Yamaha's marketing position. Currently, Yamaha sells more YZ250Fs than any of the competition's 125cc dirt bikes, and the YZ426F sells at a pace about even with the YZ250 2-stroke, with numbers not far behind the 250F.
To find out what the big deal is about these new challengers, we plucked two natural enemies from the confines of Yamaha's warehouse: a YZ125 2-stroke and YZ250F 4-stroke that compete against each other in the AMA's 125cc National Motocross and Supercross classes.