Hi guys!
Don´t know if your CSC RX3 bikes have this "rear lower fender", but I´m sharing my experience just in case.
A couple of days ago found this fender loose someway, even when the two bolts where properly torqued.
After removing those bolts found the inner 3/8" pipes, that holds the plastic frame, where broken just after the soldered joints.
Tomorrow will look for a welding shop to fix this.
Regards,
Juan Carlos.