The IS C suffers from body flex, which is most noticeable on rough surfaces.

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Small breaks and rough surfaces are eliminated by plaster of clay or lime, and then painted.

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Escalade Hybrid is remarkably composed around curves and on rough surfaces, and is a positive locomotive on a long road trip.

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What is suggested to be at work here is the concept of asperities - the idea that if you take two rough surfaces and rub them together, the peaks in one will couple with the troughs in the other, increasing friction.

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