I found out that Formula's apparently take a 27mm seatpost.
Could be possible, but not for the 1st series. All Reyn. 531 pg seat tubes take 26.4mm seat posts. You must be talking about 1990's 525 frames.
@Dutch_Cheese started
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Could be possible, but not for the 1st series.
All Reyn. 531 pg seat tubes take 26.4mm seat posts.
You must be talking about 1990's 525 frames.