Originally Posted by
dweenk
26.8
The clamping area looks a bit close - if I had a 27.0 I would try it.
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in this image the "points" of the seat binder ears look to be almost touching
would have expected 27.2
you could withdraw pillar and lightly file/sand interior of opening to get it clear of possible rust/paint/dirt
also, opening may be slightly out of round from overtightening on a too small pillar...
with pillar removed, try gently prising open binder ears with blade of a large screwdriver or similar about 3mm. present pillar may then drop loosely into tube.
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