I'm pretty sure the two motors would draw more current through the ESCs, just as if you were to connect a larger, higher-powered motor in there. Thus, you get the full power from all four motors, but you only need two ESCs to control them if they can handle the current draw (like TZ85s). But yeah, you could do a belt system I guess. Seems unnecessarily complicated when you could just have one motor per wheel.
If someone knows I'm wrong here, please tell me, but I'm fairly certain on that.
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