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.
