Old 02-09-12, 10:35 PM
  #10  
FBinNY 
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Join Date: Apr 2009
Location: New Rochelle, NY
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Bikes: too many bikes from 1967 10s (5x2)Frejus to a Sumitomo Ti/Chorus aluminum 10s (10x2), plus one non-susp mtn bike I use as my commuter

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Originally Posted by mydenimisraw View Post
Any idea how I could resolve the problem if that were the issue?
If the threads are in fact stripped an easy fix it to replace the bolt with a seat post QR unit. Most of these have shank diameters smaller than the typical bolt and can just slip through. Likewise you can just use a bolt and nut, with a thinner longer bolt.

While you're fooling with it, you should try to see the real problem. Start by fitting the post and clamping gently. look at the slot, if the top closes to less than 1/2 the width of the bottom, your post is undersized and that might be the problem. If the tube closes to where the tube touches at the top, the post severely undersized and will never tighten regardless of how muchc pressure you put on the ears.

Also see if the ears touch in the back, which isn't rare when they've been overtightened and bent. Ears touching mean that they're partly collapsed, or cracking away from the lug, so check thoroughly.

If the slot is still parallel when tightened, and the ears don't touch, it should tighten, but if not try replacing the grease with carbon assembly paste, or my favorite fix. Put coarse lapping compound (grit in grease) on the 2" or so of the post that will be at the height of the pinch bolt. When clamped the grit bites into both the frame and post making a mechanical interlock that will hole with very little clamping force. If you use the lapping compound, be sure to completely loosen the post before making even small adjustments.
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