Ahem..

Metal bearings are pretty much imperitive. The stock kit comes with those nylon (white) ones you see. whrn you upgrade the motor past 27T the nylon heats up from the increased friction. When it melts; it will stick. When it dries; it's already welded everything together.

with metal ones; you dhould get a better runtime and smoother drivetrain. Get some before you even think of running that car with a 17x2.

Chris.