Which is btw. not recommended. Brompton explicitely states in the manual that you must not mount it that way as it will lengthen the lever of the seat post, putting more stress on the seat-tube and possibly leading to frame problems.

And what is a SAP?

I assume fietsbob meant the Brompton saddle pin adaptor



It has been discontinued a while ago.

From an old Brompton manual:

"Saddle adaptor pin (125 gms)
a) mounted "pointing down", it allows the saddle to be moved up
to 40mm forward (which also makes the folded package the
most compact)
b) mounted "pointing up", it allows the saddle to be moved up to
30mm higher, albeit slightly further forward."

Yup. .. in use the tube is horizontal pointed fore or aft.. on top of the seat post.

CM Wasson (US dealer emeritus) added a common QR, so the SAP came off easily to pack the bike small ..








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