本文以實體元素模擬兩部結構相似、僅引擎吊架型式不同的速克達機車整車模型（一部為水平式懸吊，吊架與車架鎖點對吊架與引擎鎖點之連線接近水平；另一部則相對為非水平式引擎吊架）來探討吊架型式對振動造成的影響。
對應駐車的邊界條件進行設定後，使用有限元素法模態分析發現兩車對應前五個自然頻率的振動模態類似，而兩車前五個自然頻率的數據也相當接近。接著分別以兩個方向的單位搖撼力（分別為沿活塞運動方向、垂直活塞運動方向，單位為N）與單位搖撼力矩（單位為N．mm）進行簡諧分析，結果顯示車身於側向的振動響應遠小於前後方向與鉛直方向的振動。而雖然兩車的前五個自然頻率及模態類似，簡諧分析所得的頻譜響應分布卻不盡相同。
最後，假設整車為線性系統，引用在怠速情況下定扭力假設所得的搖撼力與搖撼力矩頻譜與簡諧分析結果作運算，模擬得到車架中間位置和汽缸的位移對時間分布圖及對YZ平面的軌跡分布圖。藉此觀察兩車在兩個取樣點的振動位移之異同，再與影像實驗所得結果進行比較。進而發現分析機車的振動響應必須考慮引擎搖撼力的分布方向、特定的模態的振動模式，以及車架、吊架及引擎鎖點的扭轉剛性等等因素，才能得到較全面性的模擬結果以比較摩托車不同設計造成之差異。

In this paper, solid element has been used to build the finite element model of two motorcycles which have different kinds of engine hanger and similar kinds of frame structure. The two types of engine hanger alignment are horizontal and non-horizontal, which depend on the line connected by the two joints, the joint between frame and hanger and the joint between hanger and engine, is nearly horizontal or not. The two models have been used to analyze the difference of vibration caused by different engine hanger alignment.
Setting the boundary conditions as the parking motorcycles, then the two models have been simulated with modal analysis. The results show that the two models have not only similar first five natural modes but also have close values of the first five natural frequencies. Next, the two models have been subjected to three types of input for harmonic response analysis. The inputs are the two unit shaking forces which is along or perpendicular to the direction of piston motion and the unit shaking moment triggered by the force which is perpendicular to the direction of piston motion. According to the harmonic analysis, the vibration responses in lateral direction of the two motorcycles are much smaller than the responses in front-back direction and in vertical direction. Though the two models have similar first five natural frequencies and natural modes, the result of harmonic responses are not quite similar.
Assuming the models are linear, and introducing the spectra of idle-speed shaking forces and moment which are simulated with the constant torque assumption, time-dependent displacements of two specific points, the middle point of the frame and the point of cylinder, have been computed and compared with the results of experiment. While researching the vibration response of motorcycle, not only the alignment of engine hanger but also the directions of which shaking forces distribute, the motions of specific modes, and the torsional stiffness of bushes should be concerned.

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