1. What’s the matter with the scooter’s shaking at the start
There are several common reasons for the start-up shaking of motorcycles:
1. Motorcycles Poor lubrication between the moving plate and the fixed plate of the driven pulley of the transmission system increases the axial movement resistance of the moving plate, and cannot tightly clamp the transmission belt with the fixed plate under the action of the spring, so that the driving pulley drags from the fixed plate. When the driving pulley rotates, the transmission belt is suddenly tight and sometimes light, resulting in slippage. Not only does the transmission belt vibrate and slap the side cover of the transmission case to make noise, but when the centrifugal clutch works, the power is transmitted to the rear wheel through the belt, which causes the motorcycle to start shaking.
2. The chamfer at both ends of the clutch friction plate on the centrifugal clutch is too small. After the motorcycle runs for a period of time, the clutch friction plate wears out and loses the chamfer. When the centrifugal clutch works, under the action of centrifugal force, the clutch friction plate overcomes the pulling force of the spring to open and engage with the clutch shell. Due to the loss of chamfering at both ends of the clutch friction plate, the clutch friction plate cannot be smoothly engaged with the clutch shell when it is engaged. After the power is transmitted to the rear wheel of the vehicle, the motorcycle starts to shake.
3. The working surface of the clutch friction plate is stained with oil, and some clutches are injected with too much grease. During the operation of the clutch, the grease flows out in the axial direction under the action of high temperature and centrifugal force , and then splashed to the clutch housing and clutch friction plate, when the clutch is engaged, abnormal slip occurs, and the power is transmitted to the rear wheel of the car, causing the motorcycle to start shaking.
Second, how to solve the shaking of the scooter at start
First open the side cover of the transmission case, remove the rear clutch assembly, and check whether the clutch drum wear is normal , with or without radial runout, use a caliper to measure whether the inner diameter exceeds the limit value. Then loosen the large nut on one side of the clutch and disassemble the clutch and pulley. Special attention should be paid here. There is a strong large spring in the pulley, which will eject the clutch at the moment when the nut is loosened, which is very dangerous. So it’s better to press the clutch tightly with both hands and then loosen the nut, and then slowly release it. Check the elasticity of the large spring, and check whether the surface of the belt pulley is obviously worn or not. Loosen the three clips on the clutch, remove the triangular spacers, remove the three tension springs, and the three friction shoes are fully exposed.
At this time, it was found that the friction shoe block without the tension spring could not be opened freely. When the shoe block was removed, it was found that there were three rotatable rubber columns on the bottom bracket, and the corresponding position on the shoe block had a semicircle. Shaped groove, the rubber column is just stuck in the groove when the shoe block is retracted. Its function is to reduce the vibration of the hoof and increase the smoothness of the opening and retraction of the hoof. The crux of the problem is here. These three rubber columns are much thicker than the grooves on the shoe block. Maybe it is a processing problem, or the oil stain makes the rubber column expand and makes the shoe block very tight and cannot be smooth. Open, there will be sudden opening and sudden retraction during work, resulting in start jitter. Now, as long as the three rubber columns are carefully polished, the diameter will be reduced so that they can be smoothly inserted into the groove and have a certain resistance. noise. At the same time, check whether the friction plate is rubbed and fall off, and if possible, use a balance to weigh whether the three hoof blocks are the same weight. Take a look at the belt and front derailleur by the way. Then put a small amount of grease on all rotating parts (belt, pulley, friction plate, clutch drum, no oil), carefully assemble all parts, and then load and test. OK, now let’s try it.
The idle speed is 1500r/min, lightly refueled, when the shoe opens at 1750r/min and starts to contact the clutch drum, the car begins to move forward slightly, and when the speed rises to the normal starting speed of 2000r/min, the clutch A real combination, a smooth start without any loss of torque. More importantly, it is very smooth, without a trace of jitter. You’re done!
In conclusion, the friction between the rubber column and the hoof block is reduced, so that the hoof block rubs against the drum earlier, but the speed is not enough and can not really start, the real starting speed does not decrease, so Will not affect the torque at start.
