There are many reasons for the abnormal noise caused by collision when rocking the car. Today we will learn how to eliminate the abnormal noise caused by improper decompression adjustment.

1. What is the reason for the decompression collision noise?

The arrow below is the pressure relief handle

When we push the decompression to the bottom and shake the car, we can feel obvious vibration and collision at the decompression point. In severe cases, the cylinder head cover will jump regularly at the junction with the cylinder cover.

2. How to adjust the pressure relief?

First, we rotate the flywheel in the direction of the arrow. When we feel that it can no longer rotate and there is rebound force, stop, and then adjust the decompression.

Open the small cover and reduce the pressure to the bottom to expose the adjustment thread.

Use a No. 10 T-type wrench to loosen the spare cap of the adjusting thread.

Then use a flat screwdriver to turn the adjusting thread to the left until it feels loose and no effort is required. Now start turning the adjusting thread to the right, starting from when you feel it hit something, and turn it to the right 1.5 turns.

Tighten the nut with a T-wrench and reinstall the small cover, and it’s adjusted. If you feel no effort when rocking the bike again and there is no sense of pressure relief and collision, it’s adjusted.