Yes original spec is JIS format 27.0/ 30.0, a very standard
thing. Nice ones start at $20.
That said, yes measure it as the system is designed such
that to use a more expensive (i.e. Campagnolo) headset one
cuts to the 26.4/ 30.2 format and someone may have done that.
--
Andrew Muzi
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www.yellowjersey.org/>
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