Many mountain bikes foster a loose, laid-back vibe. The 29.7-pound aluminum Scott Genius 740, however, reflects its all-business Euro engineering. A handlebar-mounted switch lets you lock the suspension fully rigid, so all momentum-robbing climbing traction is eliminated. Point the bike down the mountain and it darts around and aims beyond apexes. While not as lively as some other 27.5-ers here, this rig rewards going full-on like no other. A must if you crave speed. [$3,000;]

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