Stuck bars

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PT1029
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Joined: 16 Apr 2012, 9:20pm

Re: Stuck bars

Post by PT1029 »

Looking at the photo zoomed in, the black clamps look like they have the quick relase for adjustment at the top. At the other end it looks like 2 bolts to clamp the black clamp/bracket to the lower/outer bigger tube. Are you able to unclamp the black bracket from the lower/outer tube and remove the black bracket with the inner tube still siezed in the bracket. If you can, you might have more options for "persuading" the seized bit to become unsiezed, and more scope for applying penetrating oil or heat.
ericonabike
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Joined: 24 Apr 2008, 4:05pm

Re: Stuck bars

Post by ericonabike »

Update - managed to extract the stuck tube, together with the tube it's stuck inside, if you follow me. Essentially there is an outer, painted tube that is part of the frame. Inside that is a, steel tube that is held at each end by cartridge bearings. Inside that is an alloy tube (or possibly a solid billet) to which the bars attach, and which should slide in and out of the steel tube. There is a foot or more of the alloy tube inside the steel tube.

I've flooded it with wd40, plus gas and any other oil that was to hand. I spent five minutes heating it up, then cooling it with ice cubes inside a cloth bag. Nothing moved! It feels like it's welded together.

I've now emailed the manufacturer (in Google German) to see if the parts are sold separately. If not, or if they're ruinously expensive, I'll send the stuck tubes to The Seat post Man at https://theseatpostman.com/service/. He was very helpful on the phone.

Thanks for the advice and comments - it's quite a, challenge!
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Motorists' mantra: Cyclists must obey the law and the Highway Code AT ALL TIMES. Unless their doing so would HOLD ME UP.
Jdsk
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Joined: 5 Mar 2019, 5:42pm

Re: Stuck bars

Post by Jdsk »

Thanks for the update.

I'd back The Seatpost Man.

Jonathan
slowster
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Re: Stuck bars

Post by slowster »

Is the steel tube open at the other end? If so, can you insert a slightly smaller diameter long tube or rod, and use a hammer on that to try to knock out the aluminium tube/rod?
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simonineaston
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Re: Stuck bars

Post by simonineaston »

I've nothing constructive to add, over & above the contributons already made, other than to comment that the most stuck of the stuck things that have challenged me over the years have really felt like they were one piece, as you have remarked. Take two paces back and review the arrangment and if you really can't think of any reason that the two pieces are meant to be non-adjustable then go ahead and assume that they will seperate. From a maker's pov, it would make no sense to use multiple pieces if they were not intended to move. If for example they are doubled up for the sake of strength, there is likely to be evidence of permanent joining ie a weld or rivet. Hope that helps.
S
(on the look out for Armageddon, on board a Brompton nano & ever-changing Moultons)
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531colin
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Location: North Yorkshire

Re: Stuck bars

Post by 531colin »

If, as Simon says, you are sure the alloy bit is supposed to move inside the steel bit, then what you have is equivalent to the typical "ali seatpost corroded into a steel frame" .......with the added bonus that its a very long couple of bits of pipe you have stuck inside each other.
This is a particular sort of corrosion which produces a white substance.....some complex oxide, I guess. The stuff is crystalline, which means if you apply gentle heat for quite a long time, you can drive off (evaporate) the "water of crystallisation" which means the oxide then takes up less space, so the bits of pipe aren't quite so tightly stuck inside each other.
So thats the first thing I would try......gentle warming....it doesn't need to be hotter than boiling point.....a hair dryer or hot air gun used gently will do. Keep it hot for as long as your patience allows....its a long bit of pipe. Run some oil round the top where one pipe goes into the other....with a bit of luck you will see the steam bubbling out as the water evaporates. As it cools down, oil will be drawn into the gap. Plus gas gets recommended on here.
Second thing to try....Ammonia dissolves the oxide. You can't get hold of "880" ammonia easily in these days of 'elf and safety, but household ammonia will work.....eventually.
And finally....steel tube is made to standard sizes. (so is ali., come to that) They are still imperial (inch) sizes even now, and you can buy tube easily on the internet....."metal mania" is my current favourite supplier. You might be able to carefully grind through the steel tube and open it out to peel it off the ali. bit inside.
I don't know how the "seatpost man" works his magic.....is he is mechanically removing the post, then thats much longer than a bike one!
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