sound of the engine speed dropped to 32mph to 40 mph narrowed

GoldenMotor.com

yasin0026

New Member
Sep 16, 2011
20
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turkey
After I put renewed my bike back to burst upon the engine sound of the engine speed dropped narrowed to 40 mph to 32 mph but the engine power dropped to the same speed, I wonder why the sound narrowed?
 
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