The BridgeSorter shall not be lubricated, but you are expected to keep dirt and dust away from the hopper. You can in most cases do this by blowing as hard as you can with your mouth.
Dirt that cannot be blown off the lens, and/or dirt sitting firmly on the feed roller in the hopper, can easily be removed with a small amount of Isopropyl Alcohol on a soft cloth.
See the Bridgesorter library for additional documentation and instructions.
There is also a 5 years warranty covering faulty parts and/or manufacturing. c.f. http://www.bridgesorter.com/pdf/Warranties.pdf