In my experience, regular maintenance makes a big difference. After every run with the YIKONG YK4107 RC Car, especially in sand or mud, I clean the area around the 34T Driven Gear (Part No. 21033) to keep dirt and debris from getting between the gear teeth and causing unnecessary wear.
I also apply a small amount of grease to the 34T Driven Gear from time to time. It doesn’t need much—just enough to keep the gears meshing smoothly. When driving the YIKONG YK4107 RC Car, I also try to avoid frequent full-throttle launches or long periods of heavy-load crawling, since those put extra stress on the gear. With these simple maintenance habits, the 34T Driven Gear (Part No. 21033) should last much longer and continue to perform reliably.
