I know nothing about Bromptons, apart from how to bend a chainring on one apparently (stupidity rather than mad watts). How do I figure out what would work as a replacement? Photo attached if that's helpful. I don't know the age or model of the bike, it's a shared one that lives in a cupboard at work.
These old-school cranksets were pretty easily upgradable to the current design. Just get a suitable BB (JIS 119mm) and the newer Brompton cranksets and you're good to go. Or play around with custom hacks.
I know nothing about Bromptons, apart from how to bend a chainring on one apparently (stupidity rather than mad watts). How do I figure out what would work as a replacement? Photo attached if that's helpful. I don't know the age or model of the bike, it's a shared one that lives in a cupboard at work.