本研究根據文獻探討冷卻液能改善的潛力，針對市面上的水冷四行程機車之水箱散熱效果做相關研究，在冷卻系統添加複合碳系奈米流體(HCBNF)溶於原廠水箱精，加入分散劑GA(阿拉伯膠)再進行磁石加熱攪拌，分別攪拌3 h與超音波震盪1 h，以製備複合碳系奈米冷卻液(HCBNC)。進行不同濃度及溫度的基礎試驗，探討基礎性質最佳的濃度，實驗分別試驗base、0.02 wt.％、0.04 wt.％、0.06 wt.％的HCBNC。沉降試驗的結果發現HCBNC在靜置30天，0.04 wt.％效果非常穩定幾乎沒有沉澱現象。黏度試驗發現0.06 wt.％黏度高於其他的濃度。比熱試驗發現0.04 wt.％比熱值低於其他濃度和base。最後磨潤試驗0.04 wt.％、0.06 wt.％兩者的磨耗改善率高於base。綜合以上四項試驗結果，最終發現，較為良好的濃度為0.04 wt.％。

The study explores the potential of improving coolant according to the literature. The research on the heat dissipation effect of the water-cooled four-stroke motorcycle on the market is done by adding the hybrid carbon-based nanofluid (HCBNF) into the original water tank. The dispersing agent GA (arabum gum) was added and stirred under electromagnetic heating for 3 hours and ultrasonic for 1 hour in order to prepare a hybrid carbon-based nano-coolant (HCBNC). The basic tests with different concentrations and temperatures were carried out to investigate the optimum concentration of the basic properties. The experiments were performed on base, 0.02 wt.%, 0.04 wt.% and 0.06 wt.% HCBNC. The sedimentation test found that HCBNC was allowed to stand for 30 days, and the effect of 0.04 wt.% was very stable and had almost no precipitation. The viscosity test found that the viscosity of 0.06 wt.% was higher than all the other concentrations; the specific heat test found that the 0.04 wt.% concentration was lower than all the other concentrations and base; the tribology improvement rates of both 0.04 wt.% and 0.06 wt.% were higher than base. Based on these four results mentioned above, the study confirmed that 0.04 wt.% was with a relatively good concentration.