Could you with the SX3 flip the chassis, and mount the drivetrain on the opposite side, making the motor spin they other way - if you wanted? Might be a great tuning aid?

No, this is not possible
Are there 4 belts? 1 very small from the spur gear axle to the upper axle?[/QUOTE],

nope.. steel gears is hidden behind the plastic cover
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Ulrich Rasmussen
Denmark
Danish 4WD champion 1989, 1997, 2003, 2004, 2005, 2006 and 2007.
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