My impulse-purchased turkey :(

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Road bike seatposts are often relatively short so there may not be too much of the post stuck in the tube. Caustic soda is a guaranteed method to get it out but that will almost certainly cause damage to the paintwork. (DAMHIK).

Difficult, I know, but patience and persistence will make it come out in the end. Continue putting in releasing fluid, allied to regular attempts to twist it out. (Could take several days). I always find it easier to put the seat post firmly in a vice and twist the frame
 

GilesM

Legendary Member
Location
East Lothian
Difficult, I know, but patience and persistence will make it come out in the end. Continue putting in releasing fluid, allied to regular attempts to twist it out. (Could take several days). I always find it easier to put the seat post firmly in a vice and twist the frame

My preferred method.
 
OP
OP
wafter

wafter

I like steel bikes and I cannot lie..
Location
Oxford
Thanks all - really appreciate everyones' thoughts and unexpected optimism (for the most part) ^_^

Too many posts to quote but in an effort to address the points raised:

I'm enthused to hear it suggested that the crack might only be paint-deep. My gut feeling is that the paint will be more flexible than the underlying steel so it would be unlikely that it's restricted only to the paint; however thinking about it I rejected the first example of my Croix de Fer delivered precisely for this reason (a paint crack starting at the cutout at the seat clamp) so maybe there is hope!

I agree that the first job is going to be to get the seatpost out and inspect the tube from the inside, then probably remove the paint from the outside locally to be 100% certain that the lug is sound. I appreciate what people are saying about retaining the paint, however it's really, really tatty (the pics flatter it tbh) and I've I'm going to put some time and money into it I'll want it re-finishing.

Thanks for the thoughts on removing the seatpost; unfortunately I think it's pretty long / there's a fair amount of engagement. I definitely want it removed (both to inspect the frame and for peace of mind, while the saddle height is a shade high as it is). I'm not keen on getting it professionally removed as I want to spend as little as possible on the bike before I'm satisfied that it's viable. I hadn't heard of the caustic soda approach (I assume this attacks the ally seatpost while leaving the steel alone..?) while I'm unconcerned about its effect on the paint it seems a bit drastic so I'll consider it a last resort currently. I'm wary of applying too much force due to the potential to damage the frame as suggested by @Cycleops so I'll persevere with the paraffin and heat for now I think.

Not that it's obvious from the pictures but the retaining system on the seatpost has a 12mm through-hole that a bar can be pushed into, so I can get a reasonable amount of leverage on it (not that it's helped so far!). Really I think I could do with getting some more heat on it (my propane torch is only small so it takes a good while and of course the ally is very good at dissipating heat).

The damage to the seatstay is an odd one as it seems to continue onto the brake caliper; but underneath the retaining bolt for the brake block.. so maybe something that happened when the bike was being worked on..?

Tbh I only really bought the bike for its frame and consider all the other components expendable; so these would be sold / binned / destroyed as appropriate in favour of a nice modern groupset. The only possible exceptions being the bars (as they have a nice short reach) and the headset if serviceable. I suspect I could probably get close to getting my money back if I flogged off all the components.

If the frame does turn out to be cracked I'll make a few enquiries as to repairing it; I don't know but I'd guess this would probably involve drilling out the root, slitting the crack and brazing up the resultant hole. I also think maybe enlarging the existing hole at the bottom of the slot in the tube would help to dissuade any further cracking; although I guess a repair would always be weaker than it would have been previously.

If the frame proves to be serviceable the plan will be to get it professionally re-finished as I've done the "spray can in the shed" thing before and never got results I'd consider acceptable.. the idea of this project would be to create something I consider special that I can take out occasionally for the pleasure of riding it; as such I have little interest in keeping it as a beater as the Raleigh already fills this hole and is a lot more practical with its panier and mudguards.

This thread has given me a bit more hope and motivation than I expected; for now I'll keep tipping paraffin down the seatpost tube (good tip @chriswoody re. adding it from the BB; although I don't currently have a tool to get this out and again am reluctant to spend the money).

First step will be to free up the seatpost and inspect the frame if I can; then if I get this far I'll try to sort out the more basic mechanical issues (gears, sloppy bearings) and ride it a bit just to see how it goes. Tbh for the few hundred metres I've ridden it so far it feels very nice - responsive, light and somehow "alive" (possibly offering some compliance / damping without being harsh). It seems to fit with all the adjectives people use to describe good steel frames but I can't put my finger on exactly what specific behaviour makes it feel this way.

Anyway, nothing's going to happen with this quickly, but I'll seek to plod on as and when in the hope of making some progress :smile:
 

DCLane

Found in the Yorkshire hills ...
The crack, like others have put, may just be paint. I'd suggest removing the paint at that point to check.

You've got some decent-ish wheels, a groupset and an interesting stem at the least - depending upon what you paid that may compensate quite a way.

My "catalogue of horrors" was bought last year; a flat-bar converted Olagnero. Looked decent value for £40 but the seller forgot to tell me the seatpost was stuck. And that it was rusty throughout. I've attempted all methods to remove the seatpost and am slowly cutting chunks away when I get the chance as it's over 300mm into the frame. If all else fails I'll similarly have a groupset plus some wheels and other bits.
 

All uphill

Still rolling along
Location
Somerset
I like that @wafter .

If it was mine I'd also start with the seatpost. I'd enlarge the stress- relieving circular opening at the top of the seatpost to take out the crack (if that's what it is), clean, polish and protect the existing paintwork and then ride.

I'm not sure I'd spend the money to repaint and put on a new groupset.

Somewhere here there is a interesting report on using aliexpress cheap parts - maybe an option?
 

GuyBoden

Guru
Location
Warrington
Heat just makes it tighter. Aluminium expands more than steel. You can melt it out (it melts before the braze) but you probably need a real brazing torch for that, and a lot of practice.

The caustic soda approach is described here, and it worked perfectly: https://yacf.co.uk/forum/index.php?topic=36893.0
Yes, applying heat is no good, as mentioned by @rogerzilla heat expands the Aluminum more than Steel.

Applying cold would be better than applying heat, you could try dry ice, but caustic soda worked for me.

If the Seatpost is at an ok height for you, just leave the seatpost stuck in the frame.

Sheldon Brown's answers for stuck seat posts:
https://sheldonbrown.com/stuck-seatposts.html
 
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sittingbull

Veteran
Location
South Liverpool
I'd turn the bike upside down and spray Plusgas (using the straw nozzle) through the bottle cage bosses on the seat tube. That way you can attack the corrosion from both ends of the stuck post. Repeat as necessary.
 

grldtnr

Über Member
Since cycling remains pretty much the only thing I find interesting or rewarding (yet I can't get out on the bike much currently) I've been self-indulgently clinging to the idea of a future "neo-retro" steel road bike build; researching the intricacies of marrying an old steel frame to a modern groupset and keeping an eye on the market for suitable candidate.

Long story short after a few beers I ended up arranging to look at something that looked like a good bet. I had a good list of points to check on the day but thanks to various factors really didn't pay nearly enough attention, got stiffed and ended up buying a rotter. Spoiler: amongst other things the frame is cracked :sad:

This isn't going into projects as I'm not even sure if I'll do anything with it and it might just get written off / punted on.

So here it is; presented for the entertainment of CC; and hopefully some advice as to how to proceed once the sniggering has died down...

On paper the bike looked good:
- Evidently the work of a small / custom frame builder
- Fitted STIs and 9-speed groupset, so correct rear axle spacing to take a current 11sp setup
- Forks with an internal crown (looks nicer and apparently something usually found on higher-end bikes)
- Reasonable spec components..

In practice the bike looks less good (some of which I spotted on the day, some I only discovered when getting it home - I'm sure it has more to give):
- Cracked seatpost tube
- Seized seatpost
- Generally very tatty frame / general condition
- Won't shift the full range of gears on the back (think this is just an adjustment problem)
- Play in front hub bearings

The frame is apparently a "Mick Gray"; a name I've not heard of before and there's scant info on the net about the guy. The seat tube is 57cm c-c, the top tube 58cm c-c so it's pretty stretched compared to what I'm used to (for reference my Routier has a 58.5-ish cm seat tube and 57.5cm top tube); especially given my short torso..

As it stands, according to my shonky bathroom scales the bike weighs around 10.2kg - which I think is pretty reasonable for an oldish steel frame with a mid-range groupset.

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The bike has a full 105 5500 (I think) 2x9 groupset , which is a bit tatty but (rear shifting notwithstanding) all appears to work pretty well. Apparently this groupset was available from 1999 - 2006 IIRC, and given how complete it is would guess that it was original-fitment when this bike was new.

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On top of the frame's already "generous" reach, the bike is fitted with a silly 125mm-ish stem. I think I'd need one of around 70mm to bring the reach to the bars closer to what I'm used to..

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The headset is also 105. There's a braze-on front pump mount; although no corresponding rear mount; which I guess was probably removed when the bike was re-painted in the past. The lugs don't appear to be anything to elaborate - anyone recognise them?

View attachment 620116


The fork with its internal crown and recessed brake nut. Tyre clearance is huge. Cable guides are mis-matched..

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The front wheel is a "Rolf Vector Pro" with a disconcertingly small amount (14) of aero-profile spokes with internal nipples. These seem to have been quite high-end wheels at one stage; with the rears having a bit of a rep for fragility - probably why the one on this bike doesn't match the front. (Pic to follow as I missed this one somehow).


Pedals are LOOK Spds, which seem a bit posh (if tatty). The larger sprocket on the crankset is 53-tooth; couldn't be bothered to count the smaller one but I'd guess it's either a 42 or 39.

View attachment 620120


Compelling evidence that it's been re-sprayed; apparently Mick Gray has / had some association with API - so this would support the idea that the frame's what the stickers say it is..

View attachment 620121


More detailing of the bottom bracket shell and slightly unusual chainstay bridge...

View attachment 620122


The incorrectly-routed cables on the underside and pretty atrocious, wear-and-corrosion-courting integral cable guides.. there's no serial no. that I can see; note the single "S" stamped on the shell - given its positioning it'd not surprise me if there was some more letting under the filth..

View attachment 620123

...
Mick Gray ,built bikes locally in the Chelmsford area, a racing guy, who also rode with the CTC, mostly for friends & friends of friends,
API resprays also an Essex business, in the Epping area, I have an API spray job done by him ,seems OK
 

rogerzilla

Legendary Member
Not very. Maybe with a rusted steel post, where the phosphoric acid will soften and dissolve the rust. But, in that case, you'd be better off pouring warm citric acid into the seat tube, as you can mix it many times stronger.

Aluminium hydroxide (fluffy white corrosion) is what is jamming the seatpost here, and phosphoric acid won't do much to it. Even if some is converted to aluminium phosphate, that's insoluble too.

Caustic soda works because it doesn't attempt to get between the post and the seat tube at all; nothing effectively penetrates the hydroxide layer. It just dissolves the whole post from the inside out.
 

grldtnr

Über Member
Not very. Maybe with a rusted steel post, where the phosphoric acid will soften and dissolve the rust. But, in that case, you'd be better off pouring warm citric acid into the seat tube, as you can mix it many times stronger.

Aluminium hydroxide (fluffy white corrosion) is what is jamming the seatpost here, and phosphoric acid won't do much to it. Even if some is converted to aluminium phosphate, that's insoluble too.

Caustic soda works because it doesn't attempt to get between the post and the seat tube at all; nothing effectively penetrates the hydroxide layer. It just dissolves the whole post from the inside out.
If Caustic soda isn't used or suitable , you are only left with an engineering solution, of cutting the seatpost off ,then boring out the remains with a reamer or drill, collapsing the remains then remove, it isn't a cheap option , maybe chopping it of close to the lugs then trying to saw through the stump of the post?
I once had a post snap clean off in the seat tube, I couldn't remove what was left, so resorted to drift it down the tube to put in another post, probably not the ideal thing to do but there didn't seem another option still it did move enough down inside for me to do that.
 
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