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Old 09-25-09, 10:29 AM   #1
n8tron
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seat post trouble (bolts won't tighten)

I recently bought an alpha q prolite seatpost. After adjusting it a few times I am now having trouble loosening the back bolt, as well as the plastic front adjustment. The bolt simply turns the screw and bolt that it tightens to at the same time, thus not doing anything but turning around in place. I think the plastic ring on the front adjustment is doing the same, though that is difficult to turn anyway unless the rear bolt fully loosened.

any ideas?
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Old 09-25-09, 12:58 PM   #2
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Can you take a picture of the nut part the rear bolt screws into. The front wheel "bolt" will be hard to turn with the rear bolt fully on or close to. That's normal with that type of seatpost bolt design.
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Old 09-26-09, 11:05 AM   #3
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alright, here are two pics of what is going on... some description is in the pics.
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File Type: jpg seatpost1.jpg (91.4 KB, 65 views)
File Type: jpg seatpost2.jpg (92.1 KB, 51 views)
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Old 09-26-09, 11:34 AM   #4
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In the first picture, check to see if there's a nut inside the aluminium clamp. If not, the aluminium is stripped. Install a nut above it. It'll be a pain to have to reach in with a wrench on top to tighten, but it'll work.

In the 2nd pic with the plastic "wrench" to hold the nut, replace with a regular nut.
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Old 09-26-09, 12:39 PM   #5
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The top caption in the first photo is pointing to the nut that the screw should be loosening and tightening against but instead it just follows the screw. It's impossible right now to get a wrench around that bolt the way it is now. I'm trying to figure out a way to grip it somehow.
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Old 09-26-09, 01:08 PM   #6
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I think what danno was saying is to put a second nut on top of the first, so that you can hold it while tightening the bolt. I suppose that won't work to get the bolt out though. For the front bolt, that is only designed to be turned when the back is loose. The process is to use the front bolt to set the angle, then lock it down with the back bolt. To remove the rear bolt, I would suggest using a small, sacrificial allen wrench. Jam it in between the nut and the aluminum of the clamp and that should hold the nut well enough to break it loose.
One problem may be that the bolts look bone dry. It may be too late for this post, but always grease the bolts before you install them. You'll be able to get a much stronger clamp on the seat rails without putting as much force on the bolts.
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Old 09-26-09, 04:05 PM   #7
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You might be able to insert the short-end of a small L-shape allen-key into the top-clamp with the spinning nut. One of the hex-nut's 6 corner will jam the allen-key into the side of the clamp and lock it into place. Then you can remove the bolt and remove the clamp.

Remove the nut from the clamp and fill the hole with washers. Then use a nut on top to re-install.
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Old 09-26-09, 04:18 PM   #8
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Quote:
Originally Posted by DannoXYZ View Post
You might be able to insert the short-end of a small L-shape allen-key into the top-clamp with the spinning nut. One of the hex-nut's 6 corner will jam the allen-key into the side of the clamp and lock it into place. Then you can remove the bolt and remove the clamp.

Remove the nut from the clamp and fill the hole with washers. Then use a nut on top to re-install.
i see what your saying and I'm trying do that that, but it seems as though that bolt is actually not a hex bolt but a smooth circle that I most have been "fastened" to the seatpost and has come undone.

dare I involve super glue to stop this bit of metal?

I'll keep trying to jam it with a hex wrench. Thanks for the ideas.
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Old 09-26-09, 04:30 PM   #9
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Quote:
Originally Posted by n8tron View Post
i see what your saying and I'm trying do that that, but it seems as though that bolt is actually not a hex bolt but a smooth circle that I most have been "fastened" to the seatpost and has come undone.

dare I involve super glue to stop this bit of metal?

I'll keep trying to jam it with a hex wrench. Thanks for the ideas.
Do you mean the nut that's inside the top-clamp (1st photo)?

Last edited by DannoXYZ; 09-26-09 at 04:49 PM.
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Old 09-26-09, 04:34 PM   #10
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I would take it back and get a new one...you just bought it. In the 1st pic, the bolt looks deformed/bent and in the 2nd pic the thumb wheel is already separated from the bolt (bond failed and the threads look dry), possible broken. Would have to take it apart to really see what happened and it's possible to rig up a solution, as mentioned by others in this thread. BUT just doing a return and getting a replacement is a lot easier.
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Old 09-26-09, 04:42 PM   #11
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I would take it back and get a new one...you just bought it. In the 1st pic, the bolt looks deformed/bent and in the 2nd pic the thumb wheel is already separated from the bolt (bond failed and the threads look dry), possible broken. Would have to take it apart to really see what happened and it's possible to rig up a solution, as mentioned by others in this thread. BUT just doing a return and getting a replacement is a lot easier.
I bought it online... i'll check the return policy, but then the trouble with that is I need to get my saddle off it before I can consider a return.
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Old 09-26-09, 04:49 PM   #12
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Quote:
Originally Posted by n8tron View Post
i see what your saying and I'm trying do that that, but it seems as though that bolt is actually not a hex bolt but a smooth circle that I most have been "fastened" to the seatpost and has come undone.

dare I involve super glue to stop this bit of metal?

I'll keep trying to jam it with a hex wrench. Thanks for the ideas.
Quote:
Originally Posted by DannoXYZ
Do you mean the nut that's inside the top-clamp (1st photo)?
Ah... I can guess that they skimped on manufacturing processes and costs by not milling a hex-hole for a nut. They probably just milled a round-hole and press-fit in a knurled nut. This method cannot withstand the required torque from the clamp bolt... maybe for a couple of install/removal processes. But it'll eventually spin loose as you've found.

yeah, you can try SuperGlue to bond the nut to the surrounding clamp. Then remove the front bolt & nut completely so there's less tension on the one in back. Then use an impact-gun on the rear bolt. The fast speed can often spin free a bolt that has a loose nut on the other end.
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Old 09-26-09, 06:58 PM   #13
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I agree with DannoXYZ, but I wonder if the area is stripped somehow. You can't fit a ratchet socket in there to hold on to the top bolt while you tighten the bottom, can you? If you can just get it to press on the clamp enough so you can spin the other bolt, it should work out.
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Old 09-27-09, 12:27 AM   #14
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I agree with DannoXYZ, but I wonder if the area is stripped somehow. You can't fit a ratchet socket in there to hold on to the top bolt while you tighten the bottom, can you? If you can just get it to press on the clamp enough so you can spin the other bolt, it should work out.
I tried hard... there is barely a millimeter of edge on the front and its a little underneath the edge on the back. I threw some super glue in between the post and the knurled not. I'll see tomorrow if that helps it connect better.
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Old 09-27-09, 07:19 AM   #15
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I don't have any further hints to add to what's already been posted, but if get your saddle off the post, I would not get another post like it for replacement. That just looks like a very poor design to me. IMO
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