一是增加了行驶的危险性。小拖拉机自重比较轻,过快行驶时急刹车,拖车就会顶撞拖拉机,易造成事故。二是发动机部件磨损加快,寿命缩短。三是工作性能变坏。车速提高之后,发动机功率虽没有变,但牵引力减小了,车也就没劲了,即使是正常装载,也会形成超负荷作业,使发动机冒黑烟,不能正常工作。 One is to increase the risk of driving. Small tractor lighter weight, brakes too fast when driving, the trailer will hit the tractor, easy to cause an accident. Second, the accelerated wear and tear of engine parts, shortened life expectancy. Third, the performance deteriorates. After the speed increase, the engine power has not changed, but the traction is reduced, the car is boring, even the normal load, it will form an overload operation, the engine ran black smoke, can not work properly.