Bicycle Mechanics - Seat Post Keeps Sliding Down...

I am having a constant battle with my seat post sliding down.

I have a older 10 year old Ti frame (Eddy Merckx Ti-Ax made by LiteSpeed) that uses a campagnolo seat binder bold. I have the correct size seat post (27.2) for the bike. Lately I have to keep reajusting the seat height after so many miles and its driving me nuts! I ended up snapping the binder bolt thinking it was not tight. The seat post slides into the seat tube snugly with no play. Is there something I can use or try to keep this problem from happening? My origninal seat post was a shimano 600 and I am now using a Thompson elite aluminum one. The problem happens on either seat post.

Any help or suggestions would be greatly appreciated.

This was happening to my son. I rubbed some of the grease off the post and it seems to have stopped.

Hi,
there is a local bike shop here that has a unique way of
curing that problem. He has a plumber's tool. It looks like a pipe
cutter but instead of a blade it has a gear. Used lightly it provides a series of dents.

Works.

Clean all of the grease off a portion about 1 inch wide on the inside of the post and seat tube. Do this right at the top of the seat tube and the portion of the seat post that makes contact with this section of the tube. Then apply a liberal amount of finger nail polish on the cleaned off section of the seat post. Reinsert and tighten while the polish is still wet. This will provide a moderate grip, while still keeping the post and seat tube from getting any corrosion on it.

bfromcolo,

Tried that already, cleaned out the inside of the seat tube as well. Funny thing, the Thompson seat post has horizontal lines or ridges on the seat post I was hoping this would be a fix.

BSLeVan,

That my be an option...wonder if the wife will let me borrow her clear nail polish.:)

Is your binder bolt a bolt or a quick-release? On one bike, I found that I could tighten my quick-release on the nut end and that stopped my sliding problem. On my other bike (bolt, not QR), replacing the collar was the fix (esp. after I snapped the collar tightening it down farther).

HardyWeinberg,

My seat binder bolt is not a quick release. It is campagnolo binder bolt. It't the older frame style seat bolt.

Be careful with that Campy binder bolt. They are designed to be torqued only a few times

At 10:32 AM -0700 4/3/07, Robert Gonzalo wrote:
First of all, I would like to thank you for your website! It has provided me with lots of information and tips regarding bicycles.

I have been looking at your site and was trying to find a remedy or fix for a reoccurring problem. I have a seat post sliding problem. After a ride or two on my bike, my seat post constantly needs to be reset. It just keeps sliding down very gradually. I have a titianim bike Eddy Merckx built by LiteSpeed. The frame uses*the pinch bolt design on the seat tube. It uses a 27.2 size seat post. I have tried two different seat posts, an older shimano 600 and now the Thompson Elite seat post, but the problem is still the same.

I have cleaned out any grease in the seat tube and have re tighten the seat pinch bolt, tigtening it more and more each time to a point I have snapped the binder bolt. I got a replacement bolt so all is fine, but I still have the issue of the seat post slowly creeping down on me. Do you know of a fix or can you recommend a solution for me?

Thanks,

Robert

It is important that the seatpost bolt is properly lubricated, preferably with grease on the threads and on the underside of the bolt head.

Also, make sure that the seatpost bolt isn't running out of threads and bottoming out against the nut. If it is, adding a washer or two may fix it.

All the best,

Sheldon

Low tech suggestion: I had a similar problem with an older steel framed Cramerotti & fixed it with a shim made out of a beer can. With careful cutting and bending to form a shim that doesn't fall down the seat tube, you have to look pretty close to notice the fix.

I'd second Sheldon' suggestion about the lack of threads, though it might not seem a logical problem on an old bike. My son's just finished doing up his old BMX and couldn't get the seat post to stay put. As Sheldon suggested, the bolt was bottomming out in it's hole. A washer under the bolt fixed the problem. How'd this happen? Heavens only knows - the bolts weren't removed from the clamp, just loosened but they were now a smidgen too long.

Richard

Be careful with that Campy binder bolt. They are designed to be torqued only a few times

i mean that! i've snapped several :eek: .

ed rader

I am having a constant battle with my seat post sliding down.

I have a older 10 year old Ti frame (Eddy Merckx Ti-Ax made by LiteSpeed) that uses a campagnolo seat binder bold. I have the correct size seat post (27.2) for the bike. Lately I have to keep reajusting the seat height after so many miles and its driving me nuts! I ended up snapping the binder bolt thinking it was not tight. The seat post slides into the seat tube snugly with no play. Is there something I can use or try to keep this problem from happening? My origninal seat post was a shimano 600 and I am now using a Thompson elite aluminum one. The problem happens on either seat post.

Any help or suggestions would be greatly appreciated.

make sure the clamp still has a gap between the tabs. if not get a file in there a remove a little material. a drastic measure would be to cut off the clamp and use a salsa external clamp.

i had a merckx ex and the horizontal 6/4 dropouts were a PITA to keep a wheel secure. great bike otherwise.

ed rader

I do not believe you mentioned whether the seat post is carbon, steel, or aluminum. When my carbon seat post crept downward while riding I torqued the binding bolt to specs., which did not solve the problem. So, I put the rear reflector collar directly above the binder and it added enough extra holding power to solve the problem.