Seized Reverb

kevinharley

Hi all,

I've got a reverb dropper in an OnOne 45650b frame. The reverb itself works fine (at the moment) but the post is seized in the frame. Took to my local bike mechanic, who tried all sorts - penetrating oil in the seat-tube, leaving overnight, then heating up the seat-tube with a blowtorch and trying to twist the dropper using the locknut at the top of the outer tube. No movement at all, and he had to admit defeat!

I'm not unduly bothered at the moment, but if (when) the reverb stops working properly, seems the only way to get it out will be to destroy it ... and I'd really rather not!

Anything else I / he should try?

cooldad

I didn't think Reverbs lasted long enough to get stuck.

The problem is it's a galvanic reaction, so if properly stuck, penetraing oil won't help.

Sodium Hydroxide (Caustic Soda) will dissolve aluminium oxide, but likely to wreak havoc on the Reverb (and yourself unless you are careful)

cooldad

This has a couple of ideas that might work.

http://forums.mtbr.com/ibis/reverb-stuc ... 55218.html

mark~p

You may have heated it too much with a blow torch, boiling water is often better and you can get a good spread. Get it cool first then warm the outer up. Also brake cleaner can help a bit and makes less mess than WD40. The problem is that you do not want to wreck the seatpost at this stage. If the Reverb fails and it is still in warranty you are probably stuffed as they will not take it back mangled.........

The Rookie

Household ammonia dissolves aluminium oxide (see Sheldon brown) make a funnel using some paper towel wrapped round the seatpost and then some tank tape round that then drizzle the ammonia into the funnel so it goes down the crack.

Very surprised a Reverb has lasted long enough to seize, even more so on a hardtail!

kevinharley

The Rookie wrote:

Very surprised a Reverb has lasted long enough to seize, even more so on a hardtail!

Indeed! It is my third reverb in just over three years, so about par for the course! This one has lasted the longest, so probably only a matter of time.

So the aluminium oxide ... will that be from the reverb post? Cos the frame is steel; I thought that combination would be less susceptible to galvanic reaction?

I think the other problem in my case is that I'm not a tall chap, so most of the post is within the frame.

Any mileage in taking out the BB and tipping some penetrating oil / ammonia in through the BB shell and up the seat tube?

cooldad

Steel and aluminium is a perfect combination for a reaction.

The Rookie

Yep flipping the frame and pouring up from below is a good idea.