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My seat on my bmx turns literally on every bump. If I tap it it'll turn and normally fall off.. The teeth on the seat look to be fairly worn. enter image description here I don't really want to spend any money as it's just a bike for riding dirt jumps. I was thinking of glueing it but is there any other way? Cheers :)

enter image description here

andy256
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Mitch
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  • I can't make out what part of the seat that is. Perhaps some additional pictures ... – Daniel R Hicks Sep 07 '15 at 01:29
  • Added some more now. – Mitch Sep 07 '15 at 01:32
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    You've broken your seatpost. You need to remove the part of the tube in bike with a pair of vice grips or something and then put the saddle on a new seatpost. – Batman Sep 07 '15 at 01:33
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    It would appear that your steatpost is a cast part and a tube, sort of swaged together (supposedly permanently), and the two have separated. One could conceivably drill a hole through the sides of both and install a bolt through the hole. Otherwise the post would need to be replaced, and it may be hard to find another that would mate with that seat. – Daniel R Hicks Sep 07 '15 at 01:36
  • @DanielRHicks I might try put a bolt through then. Worth a shot I'd say. Do you reckon maybe gorilla glue or something wouldn't work? – Mitch Sep 07 '15 at 01:40
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    You could try epoxy, after wire-brushing the pieces and washing with detergent to remove any oils. Do be careful to not get any glue down into the seat tube (that the tube part of the seat post fits into). That would just make a bad situation worse. – Daniel R Hicks Sep 07 '15 at 01:45
  • From the bottom picture it kind of looks like there is no bolt to tighten the seat tube to the seat post, leading one to suspect that an oversized seat post has been hammered into the seat tube. (The seat post is the black tube. The seat tube is the red tube that the seat post fits into.) – Daniel R Hicks Sep 07 '15 at 01:46
  • @DanielRHicks there is a bolt to untighten it so it's not oversized :) and I may not try with glue then and just try put a small bolt through. – Mitch Sep 07 '15 at 01:49
  • The bonding between the seatpost and its head failed. Time to get a new seatpost, glue will bring a temporary relief and the connection remains insecure. A hole with a bolt will weaken a high load carrying point. – Carel Sep 07 '15 at 10:06
  • Given that you can buy a new seatpost for 10 dollars, I think you should do that (10 dollars is not worth getting Gadaffi'd over, by your bike). – Batman Sep 08 '15 at 02:30
  • @DanielRHicks the bolt is accessed via a hole in the seat. – jqning Sep 08 '15 at 15:41
  • @jqning - What bolt? – Daniel R Hicks Sep 08 '15 at 22:34
  • @DanielRHicks yeah never mind! I realize now that you were talking about the seatpost binder bolt. – jqning Sep 08 '15 at 22:45

3 Answers3

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Slap some JB Weld on that stub and shove it in the post. Let it sit for one day. Smack it around a little and if it doesn't pop off you'll be good to go.

jqning
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Its not exactly clear on what materials are involved. It looks like the top piece was designed with an interference fit, and pressed into the tube. I'm guessing aluminum (or is that zinc?) top piece and steel tube? It's possible to braze dissimilar materials together, but it takes some significant prep work. ($$$)

If it's aluminum to aluminum, it would be possible to TIG weld the two together. You could save some costs by removing ALL the paint from both parts within two inches of the joint before bring them to the welder. Obviously you'd have to remove the seat from the mount, and the tube from the bike frame first.

Have you talked to folks who do welding repairs? It may cost a lot less than you think. I know of one welder whose motto is "Tricycles and kitchen chairs have always been free..."

Swifty
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zipzit
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  • my dad knows how to weld so I'll have a talk to him about it and see if he thinks it would work.. I may just get a new seat post if all else fails. – Mitch Sep 08 '15 at 04:18
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Your not going to find a replacement seatpost that works with the seat.

It may be worth trying to glue it together, but that will only work for any length of time if you prepare the surfaces properly. You'll need to use a wire brush to get down to bare metal. The the seat half you can use a wire wheel in an electric drill or Dremel, the inside of the seat post will be more challenging as you'll need a narrow brush and will have to do it by hand. The surfaces will also need to be cleaned with a solvent.

You could easily spend more money on tools and materials than on a new cheap seatpost and seat. Find out if you have a bike cooperative near where you live that refurbishes old bikes. They are often a good source of cheap parts.

Argenti Apparatus
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