Have the teeth gone, or just one gear rotating inside the larger gear? if that's the case, get a centre punch and punch the two gears together on a hard vice with the punch. This forces them back together, and stops one rotating in the other, and it should work fine after that.
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Team Yokomo - YZ-2CAL3 | YZ-2DTM3 | YZ-4SF2 | YZ-2T | YZ-2DTM Worlds | YZ-2DTM x2 | YRX-12 x2
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10electric | Batley Buggy Club | YORCC | RHR | MB Models
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