Reaming seatpost tube for dropper post?

[Beeewu]

After some advice on whether this can work ..got a 1992 Marin elridge grade with a 26.4mm seatpost tube and the smallest dropper post are 27.2mm.
So i'd need to remove 0.4mm so it would fit...not sure how this the tubing is on this Marin as haven got calipers.

Has any one done this or is it a no no?

thanks
B

 

[MR OX]

I certainly wouldn't recommend it.

 

[My_Teenage_Self]

Nope.

 

[Beeewu]

thought as much..maybe grinding down the dropper post might be the way

 

[Stratoblaster]

 

[CTK]

Gravity dropper did one in 26.8

 

[danson67]

Don't do it...get a modern frame if you have to have a dropper.

Taking any decent amount of material out of a seat tube is not really viable.
Seat tube reamers and hones are just for removing and smoothing any distortion after brazing/welding, not for changing the wall thickness.

Also, with a dropper post, you'd need to remove the material for a minimum of 150mm depth, maybe as much as 300mm.
That's between 5 and 10 cubic cm of steel to remove...which is a lot of hard work.

All the best,

 

[novocaine]

I dont get why droppers are so hard to make. Its an office chair shaft with a cable attached.

 

[CTK]

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[Spudalumps]

I think I read that there was a company reeming seat tubes but imagine the cost wouldn't be economical given prices of retro frames these days