Serious question: not taking the piss...
Would using a car tire void your insurance in case of a crash?
Very good question. I never thought of that. I am sure the insurance people check that as they do check the tires on most vehicles that are a total loss or there is personal injury to see if there was a tire failure. This has been a standard with many since the Firestone/Ford Explorer debacle where over 900 people were killed due to tire failures.