Upgrade your Engine to the DAX Motor 1.5 mm
wide 081 engine sprocket counter shaft sprocket.
This 10 tooth engine sprocket allows you to run 415
chains and 081 BMX Bicycle chains for lighter
weight and more performance. Only $9.49
I have used a wall mart bmx chain for years.
They do stretch but you can use a cheap chain breaker from wallyworld as well .