Stuck seat post

romperstomper · 03-06-2024 9:36pm #1

Done the wd40 dance for a week and this effing seat post won't budge. What/who else can I bring this to get it fixed? LBS (who are generally great) couldn't remove the seat post either. Is it a lost cause?

Screenshot_20240603-223153.png

Al Wright · 03-06-2024 9:59pm

Here is a link to a thread on this subject on CTC website, https://forum.cyclinguk.org/viewtopic.php?f=5&t=16716

Your frame appears to aluminium therefore DO NOT consider any solution using caustic soda.

Gripping the seatpost in a vise, heating the frame gently with heatgun may help.

Best of luck.

Wishbone Ash · 03-06-2024 10:05pm

A bit unorthodox but this worked for me.

Put the saddle back on. Find a medium sized lowish tree in your locality with a 'Y' shaped trunk/thick branch. Place the saddle in the 'Y' and use the rest of the bike as leverage to twist.

(A bench vice might work also if you have access to one).

Plastik · 03-06-2024 10:12pm

In a similar vein, I once had a very good result by removing the saddle, clamping a long breaker bar into the saddle clamp and using that as leverage to twist free.

secman · 03-06-2024 10:43pm

I had a similar problem with a Caad 9, a few guys tried, brute force, penetrative oil, heat, freezing it.. none of the above worked . Sold as a seized seatpost bike. The lad who bought it had just acquired a new "Toy "tool whereby he would cut the seatpost level to frame and his new "toy" tool would ream it out of the frame by using different gauge "yokes" to pare it out. Excuse my terminology...I'm a pen pusher 😁

cletus · 04-06-2024 4:31am

https://www.boards.ie/discussion/comment/122217353#Comment_122217353

What your describing is a reamer. Best bet would be to buy an adjustable reamer, like in the link below.

OP, if you go this route, just make sure that the outer diameter of the seat post falls within the range of adjustment for the reamer (the link is just an example of the type of tool)

https://amzn.eu/d/bwl0PQu

If you want to try it in a bench vice, and you're in Kildare, pm me

Mercian Pro · 04-06-2024 12:27pm

Belfield Bikes posted on FB a few years ago that they offered a post removal service. I think it involved cutting the post vertically and collapsing it before removal. If I ever decide to sell my titanium bike (unlikely), I will have to investigate further as the aluminium seat post is firmly stuck!

cletus · 04-06-2024 12:31pm

https://www.boards.ie/discussion/comment/122218703#Comment_122218703

Stuck seat post? Bike's worthless, I'll take it off your hands, free of charge 🫣😉

Calahonda52 · 04-06-2024 12:39pm

https://www.boards.ie/discussion/comment/122217527#Comment_122217527

is it not the inner diameter?

if the reamer drifts from exact centreline of the post it may cut into the frame without u being aware

cletus · 04-06-2024 12:57pm

https://www.boards.ie/discussion/comment/122218753#Comment_122218753

Well it would need to be adjustable from i/d to o/d, but o/d would be more important, not much point reaming if you can't clear enough material to actually remove the post. You could always start drilling out if you needed to remove some material to get started.

Yes there are some risks involved, but about as much as wedging the saddle between tree trunks and twisting the frame around the seatpost.

magicbastarder · 04-06-2024 10:27pm

https://www.boards.ie/discussion/comment/122217246#Comment_122217246

Quite often with this approach, you're better off with a short sharp shock than twisting slowly. You want to break the chemical bond between seatpost and frame, but if you try it slowly it allows time for the frame to bend.

Wishbone Ash · 05-06-2024 6:36pm

https://www.boards.ie/discussion/comment/122221080#Comment_122221080

I probably should have clarified that it was my old fixie so I wasn't that pushed about any possible damage (which didn't happen). On a better bike, I probably would have left it to the professionals.

CramCycle · 11-06-2024 8:24am

Not a stuck seatpost, but a stuck seat post technically. On the train doing repairs and took the seat post out, putting it back on with the torque wrench and as I was tightening it up, I thought, this is taking longer than usual. Checked the setting, all good there. Eventually just stopped as it has went to far for comfort. Anyway, seat post was slightly askew, went to loosen it to straighten it and the bolt is stuck tight. Bloody internal carbon seat post with a bolt that goes in under the top tube and now it is rounded. It is sunk into the frame about 1cm and I am slowly coming to the realisaation that I have to leave the saddle askew or risk a bolt extractor. Any other ideas welcome.

magicbastarder · 11-06-2024 8:28am

it's the bolt that's damaged, and not the frame?

hesker · 11-06-2024 8:36am

Think you have to get the bolt out one way or another. Assuming it’s an Allen head I think using an over size Allen key can sometimes work. Or a torx bit or something similar.

CramCycle · 11-06-2024 2:08pm

https://www.boards.ie/discussion/comment/122244411#Comment_122244411

Yep, hopefully I didn't tighten it so much that it damaged the seatpost (also Carbon).

https://www.boards.ie/discussion/comment/122244442#Comment_122244442

Yep, alas tried the Torx, but it is so tight it also slips. Next size up Allen key doesn't fit. It is the tightness more than anything as there is still a bit of bite on the correct size allen key but when I put enough force on it, it slips out.

cletus · 11-06-2024 2:22pm

https://www.boards.ie/discussion/comment/122246215#Comment_122246215

Go with the next size up torx, tap it in with a hammer.

Other than that, you could try cutting a groove for a flat head screwdriver with a Dremel or similar

hesker · 11-06-2024 2:30pm

If you read online you’ll hear of people putting rubber bands or glue into the rounded out hole before sticking in an Allen key. I’d say you’d have to be lucky for that to work.

You might have to glue in a short piece of hex bar using some strong 2 part epoxy

CramCycle · 11-06-2024 2:34pm

https://www.boards.ie/discussion/comment/122246291#Comment_122246291

Recessed to far for the dremel idea, which was my first thought. I'll try the next size torX next but its the fact that the force will go through the frame that worries me.

cletus · 11-06-2024 2:37pm

https://www.boards.ie/discussion/comment/122246352#Comment_122246352

If you can brace the far side of the frame, it should minimise any issues, but it shouldn't take too much force, either. Probably less force than the frame takes when you're out giving it on the bike

CramCycle · 12-06-2024 6:17am

https://www.boards.ie/discussion/comment/122246368#Comment_122246368

I think someone else here pointed out the idiocy of our treatment of Carbon frames, ride them round Irish roads like they are battle tanks, place them in our cars/houses/sheds as if the slightest bit of pressure would cause them to implode.

magicbastarder · 12-06-2024 6:23am

I once did ruin a carbon seat post by tightening the clamp too tight...

Squidgy Black · 12-06-2024 3:13pm

https://www.boards.ie/discussion/comment/122248865#Comment_122248865

have also cracked a carbon seatpost from inadvertently over-tightening the clamp

darragh o meara · 12-06-2024 3:21pm

I presume you have tried to pour the WD40 through the hole in BB housing? Turn the frame upside down and spray a ton of in through hole in the BB housing and leave overnight. In the morning clamp the seatpost into a vice or something solid and gently twist the frame over and back, Ive done this on a few bikes and its worked. Failing that its gonna need some heat but not too much that you damage the paintwork. A hot setting on the hair dryer should work fine.