One brake Single-Speed fools

but if someone wants to switch to a really hard gear and overtake then they can and I can't stop that. Like downhill on London Bridge, if I am spinning and some geared guy decides to switch to a hard gear to overtake, what can I do?

spin faster, do a skid in front of them to make them keep distance, keep your elbows out to not give them room to overtake

hit them, spit at them, spread oil behind you, drop tacks behind you