For exporting to European market,and aim to the technolo-gy of WY125-17A motorcycle,we made some modifies to the circuit to ensure the side stand component of motorcycle can take back auto-matically under the unforced condition.

However in the link of last effort,the left support technique has the direct influenec on the effect of passing power and making power.

Based on the jet simulation, the effects on base pressure by cylinder annular nozzle jet as well as with side support and sting support, this paper has obtained qualitatively and quantitatively the result that sting support is of less support interference, and it can be economical as well as reliable.

Analysis of the left-supporting skill in the final put in shot put;

Major skills in shot sport are holding,sliding,pushing with force at last and keeping body s balance after finishing the whole action,among which pushing with force at last is the key that will determine the athlete s score; however,left-supporting plays an important role in the process.