The Kobuki base alone will not drift, so it is smart that the tilted inertia results in the drift. Needless to say I'm able to hack my URDF having a weightless superstructure, but I needed to fix this in a more sensible way. I tried all I'm able to take https://www.uk-exhibitionstands.co.uk/product/casonara-seg-light-box-counter-300m/