>Additionally, frames build for chain gearing (instead of internal gears or single-speed/fixed) lack tension adjustment by either a horizontally adjustable drop

>Additionally, frames build for chain gearing (instead of internal gears or single-speed/fixed) lack tension adjustment by either a horizontally adjustable dropout or a bottom bracket excenter mechanism. Sliding dropouts are undoubtedly preferable, but any modern frame with a BB30 or PF30 bottom bracket can be trivially converted to an eccentric bottom bracket.