I suppose it's not ideal, but a ramped and pinned chain ring does work fine. I'm using one with the 110 bcd fsa cranks, since 2-3 years on the Brompton, and all is fine...
I guess you are lucky, it's not uncommon for such chainring to pop out even on a fixed wheel drivetrain.
@veLLo started
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I suppose it's not ideal, but a ramped and pinned chain ring does work fine. I'm using one with the 110 bcd fsa cranks, since 2-3 years on the Brompton, and all is fine...