A customer asked me to remove a seatpost from a Geos small-wheeled bike, a Mignon.
The image above is already after the work.
The seatpost came with the complete bike from the factory,
so it's a steel frame paired with an aluminum seatpost
(and without any coating like black anodizing),
which is the worst combination for galvanic corrosion.
Got it out!
From today on, your name is "99.1% Win Rate Tool"!
There was significant corrosion deep inside, so
I cut it off.
The current owner isn't the original owner of this Mignon—
they got it from an acquaintance,
but the saddle height was slightly too high and the seatpost was seized
(the seat clamp wasn't tightened at all when I received it),
so they'd been riding it on their tiptoes.
Getting the saddle to the proper height would only require dropping it a bit,
but to reach the old corroded zone, the seatpost would have to be
pushed in almost completely to the frame,
and even if you raised the saddle by about 5cm,
there's still enough insertion length available for the seatpost,
so the current owner will have no trouble achieving
the right saddle height even if they change the saddle later.
After lightly cleaning the inside of the seat tube,
I inserted the seatpost with grease applied,
so seizure shouldn't happen again for a long time.
And if it does, the contact area with the seatpost is small,
so it should be much easier to move.
The image above is already after the work.
The seatpost came with the complete bike from the factory,
so it's a steel frame paired with an aluminum seatpost
(and without any coating like black anodizing),
which is the worst combination for galvanic corrosion.
Got it out!
From today on, your name is "99.1% Win Rate Tool"!
There was significant corrosion deep inside, so
I cut it off.
The current owner isn't the original owner of this Mignon—
they got it from an acquaintance,
but the saddle height was slightly too high and the seatpost was seized
(the seat clamp wasn't tightened at all when I received it),
so they'd been riding it on their tiptoes.
Getting the saddle to the proper height would only require dropping it a bit,
but to reach the old corroded zone, the seatpost would have to be
pushed in almost completely to the frame,
and even if you raised the saddle by about 5cm,
there's still enough insertion length available for the seatpost,
so the current owner will have no trouble achieving
the right saddle height even if they change the saddle later.
After lightly cleaning the inside of the seat tube,
I inserted the seatpost with grease applied,
so seizure shouldn't happen again for a long time.
And if it does, the contact area with the seatpost is small,
so it should be much easier to move.