Every once in a while I read some good stuff, such as your lightweight thread or your EVAP canister removal, etc. that’s why I’m here and I really do like my ninja 400. Not sure there’s another ninja 400 “sandpit” unfortunately 🤷♂️ Sorry kiwi
There is a group on facebook which is for ninja 400 racers, specifically made for the more advanced/technical/racing oriented content. It's small so there isn't much activity there, but that's because there are no questions like "what oil to use", or "which tires are best", or "how to lower my bike", or posts like "I started modding my bike by getting a Two Brothers slip-on and a fender eliminator". There are several MotoAmerica junior cup racers on there, as well as the two major vendors for all things 400 (Spears and Norton).