How fast can you take that corner? How quick can you stop? It depends on the road surface, and one riding skill to develop is the ability to judge the road surface as we approach a corner or come through an intersection where we may need to stop quickly. Following are some measurements of coefficients of friction for various surfaces to guide our thoughts. These first friction coefficient estimates are motorcycle-specific from the Master Strategy Group:
Concrete 0.55-1.2
Concrete (wet) 0.44-0.9
Asphalt 0.5-0.9
Asphalt (wet) 0.4-0.7
Gravel 0.4-0.8
Ice 0.1-0.25
Snow 0.1-0.55
Here is another estimate, taken from an engineering text on rubber/asphalt and rubber/concrete coefficients:
Asphalt 0.5 - 0.8
Asphalt (wet) 0.25 - 0.75
Concrete 0.6 - 0.85
Concrete (wet) 0.45 - 0.75
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