Bike insurers did bring in problems for modified bikes a few years ago. I had some companies unable to quote as i had more than 3 modifications. A carrier, a different seat, a screen and chrome parts. It was laughable at the time. I noticed more recently that bike insurers have told me modifications are OK as long as they are not performance parts.
At one time when i told them i had a non original exhaust, they asked why. It was hard to get through that the company has not existed for 40 odd years.
Now, meet the plod who stopped my MOT tester boy and started telling him his car should have a catalyst and quoting dates of manufacture etc. Of course, the boy had the Ford build sheet for his car stating it had never had a cat fitted. Police would never know every cars details going back to 1900 that is for certain. Whoever thinks up these funny games needs to get a life.