Author Topic: Freeing seized seatpost on old bike . . .  (Read 4644 times)

lewis noble

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Freeing seized seatpost on old bike . . .
« on: November 07, 2012, 04:02:23 PM »
Hello everyone - I recently was given a 'scrap' bike left in a flat I was helping someone clear out . . . a Saracen Ruff Trax - adult size which I think would fit my son OK.  The wheels run true, the brakes seem reasonable quality, been left out in the rain for ? weeks? but I hate the idea of throwing it out.

The drivetrain is very stiff and worn out, certainly new chain and chainring(s) needed, but with me doing some and my local bike shop doing the things I can't, it is still (just about) worth fixing I think.  But the seatpost is seized in - which makes the whole project cost more to sort out.

Any tips on freeing the seatpost??  Bike shop guy tells me that heating it does not work because the seatpost will expand more than the frame . . . .

It is getting to the point where it is cheaper to buy a new bike, but this looks a decent workhorse with components that can be stripped down etc. . . .

Any suggestions re seatpost??

Lewis
 

Danneaux

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Re: Freeing seized seatpost on old bike . . .
« Reply #1 on: November 07, 2012, 04:23:04 PM »
Oh, gooodness Lewis; you have taken on a project! :o

Been there myself, by way of helping neighbors.  ::)

I can tell you what has worked for me...  ;D

Resolve to yourself: This seatpost will not survive. A large bench vise or pipe wrench will ultimately be involved in all operations. Or a saddle (as clamp-on lever), which will become disposable as well. So will time. Lots of it. Do not expect results in less than three days' trying if the 'post is really affixed.

1) Remove the seatpost bolt. Loosening it is not enough 'cos the bolt still retains the "ears" in alignment and they need to be free to spread, no matter how little. Despite what most people actually do, I would heartily recommend not prying the seatpost lug "ears" apart. It is very easy to distort the top of the seat tube and it can initiate cracks at the base of the kerf/slot below the bolt. Besides, the source of the galvanic corrosion is nearly always lower in the frame.

2) Remove the bottom bracket, invert the frame, and squirt penetrating oil (up) the frame to the bottom of the seatpost as I do the same (down) from above. My favorite is a polymer-based solution called "PB Blaster". Kroil is very, very good as well. For more along this line, see: http://forum.saxontheweb.net/showthread.php?140464-Penetrating-oil-comparison

3) Household ammonia, same routine as the penetrating oil above.

4) Dry ice on the alu seatpost (watch your hands; it burns in a blink).

5) You can try heating the 'post. It won't remove it (it will expand slightly, if anything), but this can be enough to break the galvanic bond during expansion. Wait till it is thoroughly cool before trying again to remove it.

6) There's always the frameless hacksaw. This is brutal on the operator and, occasionally, the frame (unless one is very careful and the seatpost doesn't go in very far).

These are the methods that have worked for me in actual use. For the definitive guide, see Sheldon's recommendations here:
http://sheldonbrown.com/stuck-seatposts.html

Best wishes and good luck,

Dan. (War, plain and simple...)



JWestland

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Re: Freeing seized seatpost on old bike . . .
« Reply #2 on: November 07, 2012, 04:45:35 PM »
Dan, you forgot the creative cursing  ;D

http://www.saracen.co.uk/bikes/2012/jnr/rufftrax this one?

There's often cheap bikes on local Gumtree (I am assuming you are in the UK) and on e-bay. If you enjoy WAAAAAAAAAAAAR go for it, but this isn't a high spec bike and probably economically not worth the bother.

Seatpost is Steel on Aluminum if above site is correct...I believe heating is only for alu stuck in steel, as the steel expands but the alu doesn't. Best to double-check materials before doing anything.
Pedal to the metal! Wind, rain, hills, braking power permitting ;)

Danneaux

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Re: Freeing seized seatpost on old bike . . .
« Reply #3 on: November 07, 2012, 04:52:39 PM »
Quote
I believe heating is only for alu stuck in steel, as the steel expands but the alu doesn't. Best to double-check materials before doing anything.
Absotively-posolutely, Jawine; a very wise caution else one can end up with a Creative Sculpture!  :-\

All the best,

Dan. (...who thinks of bikes as Art...but doesn't want to contribute to making one at the expense of the other)

lewis noble

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Re: Freeing seized seatpost on old bike . . .
« Reply #4 on: November 07, 2012, 08:31:19 PM »
Thanks everyone - yes, I thought Sheldon would crop up somewhere.

It looks like a full size adult bike, with plain (non-suspension) forks and better quality v brakes than usual on cheap bikes - part of the attraction, as, if it was sorted, it should be a solid and low maintenance bike.  Should be, but I don't think it will be.  As people say, it is hardly economic unless either I can free the seatpost, or my son happens to fit it ok . . . . but a potential good steed going for scrap . . .

It seemed like a good idea at the time, but I don't think I will bother - except perhaps to practice dismantling bottom brackets etc which I have never done before . . . .there, I'm weakening already .

Thanks guys, no need for more posts.

Lewis

 

lewis noble

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Re: Freeing seized seatpost on old bike . . .
« Reply #5 on: November 24, 2012, 04:50:31 PM »
I'm sure you're all wanting to know what happened here . . . . . well I'll tell you anyway.

With worn chainrings, one with almost no teeth on, a bottom bracket that sounded and felt very rough, and all the other things, I felt I would be wasting my time and money.  So I chucked the bike into a neighbour's skip.

But, at about the same time, we had a Nepali family come to stay with us.  My wife has visited Nepal quite a bit, trekking to remote hill villages as a medical volunteer with Phase Nepal.  One of their staff is now studying here in Sheffield, and lived with us until they found their own place.

And he retrieved the bike from the skip!! - "If the wheels go round, I can ride it . . . . . just pump up the tyres for me . . . . "

As might be expected, tyres would not hold pressure.  So I fitted new tubes and rim tapes, and got started on the rest.

I tipped the bike on its side and got oil into the BB.  At least it goes round now.  I could not get the rear mech working properly - wear on chain and everywhere, and gear cable and control stuck and corroded into cable lugs.  But I got the front mech working, so I put the chain onto the middle sprocket at the rear, and he now has 2 gears - using the small and middle chainring.

Brakes are fine.

So he is happy and will coast down the hill to the University and will have a reasonable gear to pedal back up the hill.

Our Nepali friends have two children.  Another neighbour has given me one of their bikes, for the kids - chain rusty, front brake broken as the handlebars have been forced round and round . . . . cables seized . . . . here we go again . . .

Lewis
 

Danneaux

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Re: Freeing seized seatpost on old bike . . .
« Reply #6 on: November 24, 2012, 05:34:21 PM »
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here we go again . . .
Aw, Lewis....Kindness is a slippery slope -- it'll pull one right into a Lifestyle!  :D

Besides your kind act of rehabbing the bike enough for someone's very valued use, I think your post perfectly highlights just how little is necessary to get -- and keep -- a bicycle working. Not working at its best, perhaps, but...working -- steering, running, and braking.

It's worth keeping in mind when something breaks on-tour. So long as the wheels go 'round, the 'bars steer, and the brakes kinda do (or shoe-soles can substitute)...you're good, and forward progress is still made. It surely beats the alternative and is still faster and easier than walking. A loaded touring bike makes a lousy wheelbarrow (the pedals, especially, manage to rotate 'round til they're perfectly positioned to remove divots from one's shins). Even a Dandy Horse ( http://en.wikipedia.org/wiki/Dandy_horse ) beats carrying panniers out on your back! FLIZ thinks so: http://www.treehugger.com/bikes/fliz-pedal-less-bike-concept.html Much of the world does very well without cassettes or Rohloffs.

As I work to true my wheels to my usual high tolerances and adjust my hub bearings for q/r preload, I often ruminate on how my standards are unnecessarily high for basic function. Sure, I really do believe my wheels roll that much better and last that bit longer, but for most of the world, the fact they roll at all is Enough.

This reminds me...

A good friend from graduate school always used butter to lube his chain when he lived in his native Taiwan. All worked well for him till he arrived in the States and bought salted vegetable margarine, thinking it was the same. By the next morning, every link had rusted. I offered a new chain. Nope. I finally convinced him to let me remove the chain and at least get it running free again after a solvent soak and hot-oil lube in a slow-cooker. Chain went back on and all seemed well -- surface-rusty, but well. I congratulated myself and felt a bit better till I saw it a week later, freshly re-lubed with some ghee (clarified butter) borrowed from his neighbor in Student Housing. Butter worked well for him, and he was staying with it!

Kindness offered and executed is never a bad thing Lewis. Good on you for helping! A bike of any kind beats no bike at all.  Thanks for sharing "the rest of the story".

All the best,

Dan. (...who also gets pulled into these things)

lewis noble

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Re: Freeing seized seatpost on old bike . . .
« Reply #7 on: November 24, 2012, 05:59:46 PM »
Very true, Dan . . . . I would hate the sound of the chain grinding over the rings and the rear mech wheels rattling . . . but he is happy + + .

I think that there are two things that count in the bikes favour - the brakes work well and seem good quality.  And the pedals are fine and seem solid . . . . but I had better free off the pedal / crank threads and put some carbon slick in . . . so dirty hands again.  That's what they are for, I suppose . . .

Lewis
 

Danneaux

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Re: Freeing seized seatpost on old bike . . .
« Reply #8 on: November 24, 2012, 06:12:57 PM »
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so dirty hands again.  That's what they are for, I suppose . . .
  ;D Nitrile gloves, Lewis. I uh, buy them by the crate (I think I've been pulled in ever more deeply...)  :D It gets worse with kids' bikes. A person has no option but to fix those. Kids, y'know. Need bikes. Precious Childhood Memories of a bike and all that. Sigh...  :-\

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the brakes work well and seem good quality.  And the pedals are fine and seem solid . . . .
Score! You're ahead of the game, Lewis!
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but I had better free off the pedal / crank threads and put some carbon slick in . .
Nooooooooooooooo! Stop while you'e ahead, Man! :o Nothing Good awaits in that interface....  ;)

Worth it in the end, though. Nothing give the same warm inner glow. Sometimes tinged with utter bafflement, but a glow nonetheless.

All encouragement and all the best,

Dan. (who has lost count of the disconnected v-brakes he's seen...and the worn-out brake pads that develop a new lease on life and work great for awhile 'cos they've tilted into the tire sidewalls. Once seen, you can't Un-Know...and feel Responsible 'cos of the knowledge, drat it all)

lewis noble

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Re: Freeing seized seatpost on old bike . . .
« Reply #9 on: November 25, 2012, 08:00:43 PM »
Dan, Your cyclo-psycho-socio-philosophising is always thought-provoking, and got me thinking back to the mid-70s, when my wife and I spent 2 years working in a pretty remote area of Ghana, near the border with Upper Volta (now Burkina Faso).  For many, owning a bicycle was the summit of ambition and took years of saving.  Vehicles were rare and generally only owned by traders, officials and so on. 

Punctures on the stone and gravel roads were frequent, and most villages had a 'vulcaniser' - tubes were mended using old engine pistons, inverted, with glowing charcoal in the 'hollow', pressing down on a bit of old rubber onto the tube.  It usually worked.

Old Raleighs and Peugeot bikes were around (Upper Volta had been a French territory), and were much sought after but hard to find.  Then a large number of cycles were imported, I think from China - cheap, plentiful spares, easy to fix with a hammer and adjustable wrench - single speed freewheel, rod brakes.

The trouble was that the bearings wore very quickly, so rattling BBs were frequent, also people pedalling direct onto the pedal spindle, sometimes with a piece of wood with a hole drilled or burnt in to make an improvised block pedal.

People rode miles on these machines, carrying produce etc - they had to, there was no alternative.

I once saw a guy on his bike, wife on the pannier rack (sidesaddle), child strapped onto her back, load balanced on her head.  Another child on a makeshift seat on the top tube.  Then, when he got going, I noticed he only had one leg, but still he managed to get along; I seem to recall he jammed the freewheel to get the pedal up again, not sure about that.  I used to have a slide of it somewhere . . .

Perhaps that's why I try and salvage things, as I guess many of us would.  And why, as you say, for many people any bike is better than none.

Enough of all these memories . . . .

Lewis