Effection Of Dynamic Balance Of Crank-Connecting Rod Mechanism On The Vibration Of Single-cylinder Gasoline Engine In Motorcycle

Inertial force of crank-connecting rod mechanism is one of major factors, whichhas remarkable influence on vibration of motorcycle engine. In order to reduce thevibration of motorcycle engine, the relation between mass distribution ofcrank-connecting rod mechanism and vibration of engine is studied, focusing onsingle-cylinder vertical four-stroke excessive balance model gasoline engine.The relationship of excessive balance rate and balance weight angle with dynamicbalance parameters (first order inertial force) is analyzed with MATLAB and EXCEL;The difference between first order inertial force and two orders inertial force is analyzedthrough inertial force calculation; Based on established models, the effect of excessivebalance rate and balance weight angle on two orders inertial force, load on crank journal,and engine swing torque are analyzed.Study results show that: The difference between first order inertial force and twoorders inertial force is obvious; Determination of excessive balance rate and balanceweight angle is related with two orders inertial force, load on crank journal and engineswing torque; The max load on crank journal and max swing torque should be reducedfor low speed engine, The force of sensitive direction (vertical direction) should bereduced for high speed engine, and considering max two orders inertial force, sum oftwo orders inertial force and sum of load on crank journal.Study results are applied to an actual product, all of calculations, test results andthe subjective feeling show that adjusted crank helps to improve the engine vibration.This paper can provide a reference about selection of dynamic balance parameters forthe excess balance mode single-cylinder vertical engine.