This was the first Yamaha factory motocross machine with a 4-stroke engine. It was developed in an attempt to provide the same level of lightness and performance as a 250cc 2-stroke …

Then came AMA Motorcycle Hall of Famer Doug Henry on a shocking full-factory prototype from Yamaha: the YZM400F. The YZM launched the modern four-stroke revolution and proved …

It was a different world in 1997. Two-strokes ruled the roost, and although some small manufacturers had good luck with four-strokes, they were off-beat novelties. Then Yamaha …

I’m not going to turn this into a two-stroke four-stroke debate, but this bike was a 100% prototype machine and went against every production rule in the book. Because of these freedoms, …

Aug 30, 2013 · Reading some old bike mags and came upon thos article about the original yzm400 Doug Henry supercross works bike. Man, this is still one of the best looking 4 strokes …

Jan 8, 2015 · The YZM 400 is the real deal: a 1997 Yamaha works engine. It's the engine that changed history, and you could say the engine that killed the two-stroke. The engine is single …

This 1997 thumper changed dirtbike racing as we know it. Doug Henry proved that four-stroke could win against two strokes. In 1997 a two stroke was seemingly...

Oct 27, 2010 · Does anyone have any specs on the YZM400 from 1997 that doug henry was riding? I've heard all kinds of things from searching that it was -426cc -500cc -550cc and that it …

世界選手権500ccクラスに参戦したアンドレア・バルトリーニとピーター・ヨハンソンがそれぞれ4回、2回のヒート優勝を果たし、アメリカのAMA選手権スーパークロスの最終戦では、 …

Oct 12, 2016 · That the YZM is uncompromisingly trimmed for maximum performance becomes clear as soon as you kick off. Only an energetic kick brings the extremely highly compressed …