4XX and 4XXX Roomba ball bearing mods
Although the earlier model Roomba brush deck did not suffer the same fate as the Cleaning Head Module in the 500/600 Roombas they still suffer from some debris entry into the brush gear assembly as well as the diameter of the gear shafts wearing down while the opening wears larger. I offer brand new brush decks both single and dual dirt detector hole models with the 2 brush ball bearings installed for your 4XX and 4XXX model Roombas and the Dirt Dog brush deck that has no Dirt Detector . Just specify one or two Dirt Detector hole brush decks when ordering a 4XX, 4XXX Roomba or that you are ordering the no dirt detector Dirt Dog brush deck. The decks are $98 including USPS shipping. Send a paypal to: firstname.lastname@example.org
Also available for the 4XX, 4XXX, and Dirt Dog brush deck, is a complete gear set with the 2 brush ball bearings installed. You can order this option for $65 including USPS shipping. Some work is required to install the bearing mounted gear set into the brush deck gear case. Enlargement of the two openings (Large brush, and small brush) Just paypal to the above email.
I also offer just the 2 sealed ball bearing set so that you can install the bearings in your own 2nd Gen or earlier Roomba. There is additional tooling required to both the two main gears and the openings the bearings are installed into. Just paypal me $28 to the above email