Repair of side brush motor Vorwerk VR100 (part 3 of 4) - info in the description!

Description valid for the whole set of videos.
I used a PU (polyurethane) belt which I cut to length and joined using heat to replace the broken O-ring of the VR100 (an usual issue after some years of use).
The calculations I show in the video are in theory correct, but I assumed way too much stretch and probably some measurements were wrong. In any case, the motor with the 3 mm belt could not run, too much friction even after enlarging the hole in the plastic.
When I used the 2 mm belt everything went fine.
The motor is now running very well and I expect the PU belt to last much longer than the original one.
Later I replaced also the LIDAR belt with the same 2 mm PU belt. Also working fine.