A constant, excessive lean condition will cause damage...
That said,... most pipes blue from overheating while idling too long,... or while diagnosing a running problem,... or during an excessive hot spell, humid spell, mountain ride, etc... and the blue won't go away until it is removed...
A blue pipe, means you are a rider.,.. traffic, weather, distance, be darned...
Judge your jetting by how your bike runs,... not by the color of the pipe...
See my tuning guide in the Tech section for tips...
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