Your Trophy has a stuck caliper? Take it to the dealer because there is something seriously wrong if a new bike has a stuck caliper. Bikes that haven't undergone routine brake maintenance usually don't get stuck--even after many years of use. If you follow the manual you should never get a stuck caliper. I've restored several old bikes and broke the piston free by disconnecting the brake line and using air pressure, but beware it could shoot across the garage. Once its free I'd remove the old seals, then clean it using new brake fluid. If there is any stuck on gunk you can use something like simple green to get it out. Any corrosion on the caliper or piston and they need replaced. Once you have it clean, lube the new seals and install them. Coat the piston with brake fluid and insert it in the caliper.