Does insurance cover expire when driving without BE?

Hello to all legal experts, I have been busy for a few days with the legal situation in connection with the installation of an exhaust without ABE. The consequences if you are stopped have already been sufficiently discussed. But what if you accept these risks and nevertheless install an exhaust system without ABE and thus an accident happens. The modified exhaust is certainly not a safety threatening part of the vehicle and therefore the question is whether someone knows whether the insurance Does insurance cover fail (in case of culpable driving behaviour or in case of an accident without fault)? Does anyone have any experience? Greetings HarleyDay