In the world of motocross, this year’s most highly anticipated machine is Yamaha’s all-new YZ450F. All kinds of crazy rumors about the bike have spread across the internet, and there’s some real doozies out there. In this video from Yamaha, multi-time motocross and supercross champ James Stewart debunks some of the crazier rumors, with special guest appearances by Valentino Rossi, Ben Spies, Colin Edwards, James Toseland, Jorge Lorenzo and TV personality Erin Bates.

What, you mean it’s not powered by a 1.2-gigawatt flux capacitor? will get a chance to see the new YZ this week in a private unveiling, and we’ll unleash full details when the embargo ends on September 8. Stay tuned!

Hit the jump, watch and learn.

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  • Great ad! I hope Yami comes out with some big, exciting changes. IMO, they had the most revolutionary gen 1 racing 4 strokes (of recent era). Everyone seemed to catch up with Honda taking a big lead in recent years (look at MX starting gates for proof). I think they have the internal resources to engineer some crazy new stuff that should help get them back to the top again. Well, they should at least be winning with Stewart regardless of what they have him on.