There are a couple I have seen, from Velo Orange and Soma, that are long enough so that almost has to be the designer's intention for how they are used. IIRC the Soma one is 250mm+ in length. No reason I can see why it is not the same as using a long Nitto Technomic quilll stem to raise the bars. The ones I have seen have a minimum insertion depth marked on them, the same as a quill stem.
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Gear Hubs Owned: Rohloff disc brake, SRAM iM9 disc brake, SRAM P5 freewheel, Sachs Torpedo 3 speed freewheel, NuVinci CVT, Shimano Alfine SG S-501, Sturmey Archer S5-2 Alloy. Other: 83 Colnago Super Record, Univega Via De Oro
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