reverb has “welded” itself inside my Giant reign carbon frame.
Any ideas to get it out?

Seatpost man would be my first call.

Seatpost man

I want to know the seatpost man’s secret method….. An spies nearby?

After trying various things I ended up using some ski/snowboard base cleaner, which is basically a citric acid thing (lemon juice might do as well). Soak for ages. Then tried to use the bike as lever and a hell of a lot of effort and swearing, and lot of loud squeaking noise that sounds like someone being murdered. Eventually started shifting.

That was with a regular alloy post, not a dropper, in carbon frame.

Since then, carbon assembly paste applied to any post I stick in a carbon frame. Even alloy in alloy frames (one post I had recommended doing that for any frame). Less clamp force required and the paste may be helping avoid the bonding.

Seatpost man would be worth a shout.

cheers, anyone got his number?

https://www.facebook.com/theseatpostman1/?hc_ref=ARSeqjWQDU5eMv0GDw-SuDtDS11V2iyKIDKm9Hy6ovMRSWkSLPP1pIlGo1tA_rzVHm8&fref=nf

https://www.ebay.co.uk/i/401231504766?chn=ps&dispItem=1&adgroupid=51318944048&rlsatarget=pla-350112627093&abcId=1128956&adtype=pla&merchantid=7395854&poi=&googleloc=9046950&device=m&campaignid=857338527&crdt=0&ul_ref=http%253A%252F%252Frover.ebay.com%252Frover%252F1%252F710-134428-41853-0%252F2%253Fmpre%253Dhttps%25253A%25252F%25252Fwww.ebay.co.uk%25252Fi%25252F401231504766%25253Fchn%25253Dps%252526dispItem%25253D1%2526itemid%253D401231504766%2526targetid%253D350112627093%2526device%253Dm%2526adtype%253Dpla%2526googleloc%253D9046950%2526poi%253D%2526campaignid%253D857338527%2526adgroupid%253D51318944048%2526rlsatarget%253Dpla-350112627093%2526abcId%253D1128956%2526merchantid%253D7395854%2526gclid%253DEAIaIQobChMImuP2trOM1wIVggrTCh1jQQduEAQYASABEgK74_D_BwE%2526srcrot%253D710-134428-41853-0%2526rvr_id%253D1345685882875

My mate had the same bother, I sprayed it with ac-50 and it was free the next morning.

Don’t bother with Coke or citric acid – aluminium oxide corrosion requires a strong alkali to dissolves it, so better with something like ACF50 anti-corrosion spray. See if you can get access to the inside of the seattube via the BB shell and apply liberally. Thermal shock by pouring boiling water on the frame might help the fluid to penetrate.

cheers all, going to try acf50, then to seatpost man if that don`t work..

My son is friends with his and i used to know him – he does not remember me- from back when we BMX ed – his dad built the track.

No idea what he does as he aint going to be telling me
Cool story eh.

What’s the general consensus for freeing an aluminium seat post in a steel frame? caustic Soda? Good too re the ACF50, will keep that for future.

ttps://www.sheldonbrown.com/stuck-seatposts.html

Caustic soda for steel/aluminium- nasty stuff but effective

The reason the post is stuck is due to a build-up of aluminium oxide corrosion between the frame and post – the white oxide crystals effectively mechanically ‘lock’ the two together. To dissolve the aluminium oxide you need a strong alkali – in this respect Coke and citric or nitric acids are just useless. You can use excessive mechanical force but I have seen frames broken this way. Caustic soda is pretty drastic – it may damage the seatpost plus there is probably an aluminium alloy sleeve inside the frame that could be damaged too.

You can read my trauma here. In short, I had a local bike mechanic, with a good reputation for removing posts, cut it out for me. This worked out a fair bit cheaper than posting the frame to Lancashire and I’m pretty sure that, even then, the post would have needed to be sacrificed.

Yours is slightly different however as where my post cost £20 to replace, yours is more like £200 and I’m guessing you’d rather not hacksaw it off if you didn’t have to. From my own experience, I tried everything to get mine out and nothing was shifting it. Even then, I was applying as much twisting force through the post as I dared apply on a carbon frame, but with a Reverb, I’m pretty sure that this much twisting force would have damaged the post.

In short, I’d probably send it straight to the man in Lancashire if he thinks he could save the seatpost.

Time for my warning again – Dropper seat posts are notorious for getting stuck. They tend to not be moved once installed unlike a regular post with a QR, so are more prone to corroding in place. Once stuck they are very difficult to remove without damage, if you try applying the same twisting or slide hammer etc. methods that you could use for a regular post then the dropper will likely be permanently damaged. Add to that the fact that they are £££ means I check mine after every other ride, either taking it out and re-greasing it or just loosening the seat clamp and twisting it a bit to make sure it’s still free.
Learnt from bitter experience.

Top tip: Its worth setting up a reminder in your google account (for example) to check and grease every month.

Do not use grease in carbon frame

Do not use grease in carbon frame

Not quite sure what you mean here, but I would always use carbon paste in carbon frames, especially with alloy seatposts. They have the double benefit of reducing the tendency to seize and, due to their inherent friction, tend to need far less clamping torque to secure, something that is especially important with dropper posts as they often stick when clamped very tightly in the frame.

Well grease does not equal carbon paste.

Very different products.

I dont know where you live but the mechanic at Leisure Lakes Notitngham seems to have the skill. He got a very stuck one out of a frame for us for 30mins labour charge. Very grateful we were

Carbon assembly grease is white grease with polystyrene granules in it, similar to what’s in the facial scrub ‘er indoors uses. The granules grip the post and allow you to use a lower torque on the clamp bolt.

Cheers, applied some ACF 50 , let it soak for 4 days and it eventually moved and I got it out. Very heavy corrosion which I have tried to emery cloth down. Its still there but I have applied carbon assembly paste and move the post after every ride to make sure it doesnt happen again.
Thanks all

survivor » I want to know the seatpost man’s secret method….. An spies nearby?
My son is friends with his and i used to know him – he does not remember me- from back when we BMX ed – his dad built the track.

No idea what he does as he aint going to be telling me
Cool story eh.

Fascinating. Thanks for sharing 🙂

Liking the sound of this acf50 stuff. Might try a tin. Got a few stuck seatposts in frames at work I’d like to shift.

I am full of such anecdotes 😉

I know a few bits – not enough to do it or even really know what he does but i do know what he does not do but wont be sharing – spoke to him after this thread …see told you full of them 8)

I’m glad I saw this post today, I am about to fit a new reverb I picked up recently and completely forgot about carbon paste! Will pop out at lunch to get some!

My current dropper is shimmed so doesn’t touch the frame so I never worried before.

Hmmm, my frame is alloy so shouldn’t be a problem although despite being cheap it seems to have disappeared.

I had thought that service intervals would be enough to keep it from seizing – probably will be OK with grip paste in there too. Fingers crossed!

A relevant (I think) video, touching galvanic corrossion, assembly paste… : https://www.youtube.com/watch?v=wU9jbwVuSCQ

Apparently the best way to get them unstuck would be to get a large enough temp difference between the post and the frame.

Apparently the best way to get them unstuck would be to get a large enough temp difference between the post and the frame.

I poured cans of freezer spray into my seatpost and nothing would make it break the bond with the frame, so while it may work for some, it certainly didn’t for mine. I cooled mine from the inside-out (hoping that the alu post would shrink, but the carbon would be stable) and had it so cold that the frame was white with frost. I didn’t try dry-ice, but I’m pretty sceptical it would have worked for me.

Being honest, I was pretty worried about applying a lot of twisting force to the post with the frame that cold as I didn’t want to risk the whole thing snapping on me!