Hey, don't shoot the messenger. I am only pointing out what is wrong AND how to fix it. I own one of these chain cases as does my son. Therefore I fix them both. It is definitely a weak part of the sled, but if serviced yearly with a $3 bushing, a tension adjustment, and an oil change, it will stay together. Not sure if it will at sustained 200Km/hr like some want to do, but for this old guy it does.
I have had my share of 2-stroke engines cold seize, piston melt, loose rod, broken stator, cracked flywheel, etc, etc, etc. I know how to fix them.