US has more motorcross similarity with bumps and jumps with chicanes and big air time. Euro is more rally course oriented with their dirt and grass tracks and bumpy and rough surfaces. Recently though Euro tracks have been integrating US big jumps and technical sections as to keep up with the US drivers and thier ability to adapt quite easily due to the familiarity of the tracks they run in.
A big example is the recent Worlds in Jakarta...take a look at the top five drivers.
Yannick is an exeption...he prolly lives next door to Xray's test track.
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