Reverb stuck in alloy frame, tips, more aggrssive chemicals?

As per the title the reverb is stuck in my alloy Bronson.

It’s currently functioning fine, but I’d like to free it from the frame.

I’ve stripped the bb out and I’ve had plus gas soaking for a few days, before that I had the tube full of vinegar. I’ve tried heating it.

Tips appreciated (with regard to solving this)

Send it to the seatpost man

Caustic soda…

[/maniacal laughter]

Simon, I think I’d do that as a last resort if/when the reverb stops working.

Caustic soda, right oh. I’ll crack on with dropping some in….. 🙂

Soak in coke for 2-3 days.

Q: Is a reverb sealed at the bottom + how do you /bash/twist a dropper post?

Plusgas from your local motor factors

Very limited bashing/twisting with a dropper post…

It’s got plus gas soaking in it now. Tried again tonight with some wiggling and shock. Not budging.

Freeze spray has been recommended to me.

I’ve got a reverb stuck in a steel frame just now – plusgas soaking at the moment then plan to attack with freeze spray and hot water a few times to try to free things up.

Tape wrench.

+1 The Seat post man.

Sudocrem

All of the above with immense brute force got my last stuck seatpost out…

… but I wouldn’t do the brute force with a Reverb. Needs twisting force and it will snap the top off probably.

Though maybe clamp the post below the collar in a vice somehow and twist the bike.

If you get it out, next time slap a load of carbon assembly paste on the post part that goes in the frame (doesn’t matter if there’s no carbon involved). Helps avoid the bonding, and you reduce the clamping force required.

Penetrating oil from Screwfix freed an alloy post in a steel frame that was 25 year plus.Its to do with getting something between the two materials and soaking in and providing lubrication.

Q: Is a reverb sealed at the bottom

A: No.

There’s a small breather hole that leads to the void between inner and outer parts of the post where the sliding bushes live.

I’d suggest Plus-Gas or diesel applied wherever you can get it between the post and frame together with patience. When the patience runs out, tip a kettle of boiling water over the seat-tube and try brute force* – or just send it to the seatpost man!

*if you twist the saddle hard enough in an anticlockwise direction, the top of the reverb will unscrew – FACT!

Acf 50

Never tried it with a bike but good with landrover steel/alloy issues

*if you twist the saddle hard enough in an anticlockwise direction, the top of the reverb will unscrew – FACT!

Yep. You can try and turn it clockwise using the flats on the collar but good luck turning it anti-clockwise without unscrewing the head.

We gave up trying to get one out of a frame (after realizing the above information….) despite spraying really good penetrating oil into the seat tube. Then after a couple of weeks of the bike hanging upside down, someone joked that if he undid the QR, the seatpost would now move easily….and it did! Patience is a virtue 🙂

ACF50 is probably your best bet.
Pour Coke in there if you want to make it sticky 😆 because phosphoric acid is near useless on aluminium oxide.

I found innotec de block amazing stuff!

No help to the OP but I’ve mentioned this before, dropper posts are terrible for getting stuck because most people install them and leave them in situ for years. With standard posts they were at least sometimes I presume dropped out of the way. And then when they get stuck, you can’t use the normal brute force methods on them. I make it a habit to give my dropper some movement every time I clean my bike.

picolax

*runs off in panic to check Reverb which I haven’t bothered taking out of alloy frame for about 18 months*

This did have carbon paste on it (2 years ago+) but as you say it’s hardly ever moved in that time.

I’ll continue soaking. I think I’ve started to see some fluid seeping through the collar. Hopefully the plus gas is starting to make its way through.

Yep the collar will untighten as will the post with some torque on it.

Have you tried riding it with the clamp slackened? might start to ease it on its way?

atf and acetone works wonders.

might take your paint off though 😀

Have you tried a strap wrench on the body of the dropper yet? Worked on my command post when it decided it wasn’t going to play and no nasty damage…

Silkolene Silkopen. It’s a graphite penetrating spray. Works wonders on any seized metal components.

wee on it

I’m amazed that you’ve had your Reverb untouched in 2+ years considering the faulty percentage of Reverbs on the market..

Have you tried riding it with the clamp slackened? might start to ease it on its way?

This might be a solution, it works on pedals and crankarms. -think brakebumps+not standing up/lowering post.

There is a guy in Chorley who specialises in seatpost removal, used him a few times, if you are interested, let me know and I will forward his details.

Thanks for the suggestions of atf and silkopen.

It’s difficult to get anything on the post shaft as only 1cm is visible between the collar and seat clamp.

It’s been ridden the last 2 rides with the clamp undone (but not since I’ve been soaking it). I may reassemble and ride it again.

Yep, it’s a reverb that’s not gone for warranty. Nor has it ever needed bleeding or air topping up.

Just leave it as it’s still working?

I’ve found after coming back to this bike (been riding something else) the seat is a bit low, and ideally I’d like to move it up.

It’s a reverb, it will break at some point.

coke

or just leave it.

see also https://www.amazon.com/IRWIN-VISE-GRIP-Original-Locking-27ZR/dp/B00004SBCB

these dont crimp or mark surfaces (unless your really ham fisted with them) – use them all the time making up tools allow good rotational torque.

Why not a freeze spray on the post and a heat gun on the tube (on the gentle setting)?