My Bissell Powerforce vacuum which I have used for many years started making a knocking noise almost like a chainsaw when I tried to use it. I took out the old roller and ran the vacuum to make sure the motor wasn't making any noise, then I disassembled my old roller and replaced the bearings, which made no difference. I finally bought a brand new roller and now the vacuum works great. There is no knocking sound at all. Easy installation: only four screws to remove the plastic protection and a small rubber band to wrap around the roller. Very happy with my purchase.
Xiaomi Mi Robot Vacuum-Mop 2 Lite RU robot vacuum cleaner, white
198 Review
Xiaomi Mi Robot Vacuum-Mop Essential Robot Vacuum Cleaner, white
284 Review
Dyson V8 Absolute: The Ultimate Cordless Vacuum for Effortless Cleaning
142 Review
Robot vacuum cleaner Roborock S5 MAX Global, black
298 Review