• Good point... Headtube is 318mm so might end up with some wood+hammer tappy tappy action.

    Forks / steerer tube may be a bigger problem than head tube & tools.
    I remember the longest steel steerer tube Reynolds / Columbus used to be just 300mm.
    I haven't seen any longer modern forks either.
    Of course there're plenty 6 m long steel tubes that can be used.
    So, you've got to use a custom fork I guess.

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