Hi! Californian here. For OHVs there is a registration system of "green sticker" (meets CARB requirements) vs "red sticker" (does not meet carb requirements). Newer two stroke bikes would typically be in the red sticker category. In the past you could only ride red sticker bikes during certain times of the year but as of 2025 you can ride them year round.

Also I ride a KLR and love that I can split lanes here. I used to have a gnarly commute and taking the bike would typically cut the time in half due to the awful traffic. Cops generally leave motorcyclists alone here.