Why can the coach leave without refueling the door?

Starting at idle speed (without stepping on the accelerator) is not the patent of driving school coaches. In fact, most manual household vehicles can start at idle speed. If not, it is a question of level. Therefore, many years ago, the driving school relatively increased the idle speed for this problem (which was common during the carburetor period) to improve the idle speed and gain more power, thus overcoming the problem that novices could not control the clutch correctly! In fact, our self-use grocery car can also start at idle speed, which is not a profound skill; Theoretically speaking, it is the most ideal way to start the clutch by controlling (not stepping on the accelerator), because this way does the most harm to the clutch, but from a practical point of view, this way is simply stupid, because even an old hand will stall as long as he lifts the clutch a little; Therefore, after we leave the driving school, we often cooperate with a pedal when starting the vehicle, which makes it easier to push the vehicle out and reduce the difficulty of starting! As shown above, this is a structural diagram of a manual transmission. The clutch is disengaged (stepped to the bottom) and the clutch is connected (the foot is lifted), so when we lift the clutch pedal, it is actually connected; Therefore, the engine power at this time, whether the vehicle can overcome its own weight and complete the start is very important! In this process, we step on the pedal to the end, and the rotation speed is about 1000 rpm, so that the engine output torque becomes larger and it is easier to start! Only in this way, the speed difference is even greater (the left and right clutch plates in the picture, the left side turns and the right side is stationary), so idling is the most scientific and stupid way to start! In fact, there is no need to step on the accelerator at the test center of driving school. When I was learning to drive, I was not allowed to give oil. Even if the slope rises, I'm still not allowed to oil it. I'm worried about semi-linkage control. As for the idle speed of the driving school car, it must be improved, because it is a carburetor car! The purpose of increasing idle speed is to reduce the difficulty of operation. It is not impossible without increasing the idle speed, but the clutch will inevitably stall without increasing the idle speed. Of course, you can still control the beginning! The current coach car does not adjust the idle speed. In the past, carburetor cars had a good idle speed. Second, the current coach cars are all EFI machines (manifold and direct injection belong to electronically controlled injection engines). Although the idle speed can also be adjusted, it must be adjusted by computer. It is difficult to operate, and it is easy to cause other mismatches, so the current coach car generally does not increase the idle speed! As for why you can walk without stepping on the accelerator, in other words, it seems easier than a family car. Its family car is also easy, but it can refuel the driving school. Who will insist on starting with clutch? So I think the family car can actually walk without stepping on the accelerator, just the feeling of some friends; From another point of view, cars in the carburetor era are very lightweight, and any car can reach about 1.7 tons, and its power performance is not ideal. It is really difficult to start without increasing the idle speed and lifting the clutch. Now, things are different. Driving school cars are generally around 1.2 tons, and the power is higher than in the past. Driving schools can easily operate without increasing idle speed! Similarly, the family car can walk without stepping on the accelerator and only lifting the clutch, but few people will use this method! .