I'm at work and my RC10 and 'Rat are at home so I can't check but doesn't the motor guard fit in the same way on a B4? They don't break - well not often - so wouldn't it be an idea to mimic that layout. As DCM said earlier in the thread the issue is not helped by the gearbox mounting allowing some flex, but the plate being too stiff and thin to do the same hence it just fractures. I'll be fascinated to see how long mine lasts under the stresses of the kit motor
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