Clarifying
If I take the cog off the old coaster wheel, will it fit on the new freewheel?
Because braking back pedal would unscrew it, coaster brakes will not have a threaded cog .. on a threaded hub.
So you buy a wheel with a freewheel threaded hub & a 1 speed freewheel .. you can get the same tooth count ..
as the cog on your coaster brake hub, 18t as you say, for the same gear ratio.
the cog is part of the freewheel.. not separate..
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