Seat clamp won't tighten
09-13-20, 07:23 PM
#26
Old Bike Craphound
Since the bolt you have from another frame has the same thread, it should be possible to find another bolt with a shorter shoulder, which should then be able to get tight. To confirm this, get a few more washers the same size as what you have and put them on the bolt side and see if the clamp closes without a seatpost - this confirms what is going on. The washers cause the bolt shoulder to be held further away from the nut (that you cannot remove), so you should be able to tighten the seatpost clamp. Adding washers is the easiest way to address the challenge, and presents no risk to what you have regardless of the cause of the problem.
I agree that finding a way to remove the nut makes sense, but it should not be necessary, as the way it is stuck is not the cause of your problem - it may be too long for this clamp (so ideally it should be replaced with one that fits the clamp), but I cannot see how it could be too far into the socket, because it should be all the way in when working correctly.
-Will
I agree that finding a way to remove the nut makes sense, but it should not be necessary, as the way it is stuck is not the cause of your problem - it may be too long for this clamp (so ideally it should be replaced with one that fits the clamp), but I cannot see how it could be too far into the socket, because it should be all the way in when working correctly.
-Will
09-13-20, 08:35 PM
#27
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Funktopus
Both bosses of the seat lug have been compromised, the washer has been smashed into the boss/bore and lessened that side, the female side has spun the key to some degree and also been tightened to the point where it has cut into the boss and lessened that side as well.
I would venture the binder bolt present is not the original, never was correct and too long to begin with, hogged out both bosses with out ever clamping close to proper.
Those nice sturdy aftermarket ones with CrMo stamped in them are the opposite of Campy's, they almost never break, if they are too long they will take a lot torque without breaking and if too long will spin and gouge the bosses thereby making it loose without breaking but of be very tight to the wrench while not clamping.
A carefully installed shorter bolt should solve this and at this point I would make sure to use a wrench on both sides to make sure no more gouging happens, actually I would grind the key off to make sure as well.
You can thread the male part in a few threads and use it to carefully tap out the female part if its long enough, if not find a longer bolt the fits the female part and carefully tap it out after threading it in a few threads.
Both bosses of the seat lug have been compromised, the washer has been smashed into the boss/bore and lessened that side, the female side has spun the key to some degree and also been tightened to the point where it has cut into the boss and lessened that side as well.
I would venture the binder bolt present is not the original, never was correct and too long to begin with, hogged out both bosses with out ever clamping close to proper.
Those nice sturdy aftermarket ones with CrMo stamped in them are the opposite of Campy's, they almost never break, if they are too long they will take a lot torque without breaking and if too long will spin and gouge the bosses thereby making it loose without breaking but of be very tight to the wrench while not clamping.
A carefully installed shorter bolt should solve this and at this point I would make sure to use a wrench on both sides to make sure no more gouging happens, actually I would grind the key off to make sure as well.
You can thread the male part in a few threads and use it to carefully tap out the female part if its long enough, if not find a longer bolt the fits the female part and carefully tap it out after threading it in a few threads.
Last edited by merziac; 09-13-20 at 08:42 PM.
09-13-20, 08:47 PM
#28
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A word of caution...when things do not go together as planned sometimes brute force is not the way to proceed...can the portion of the binder bolt left in the seat post lug be pushed back in? It looks like the BB hole is galled along with the mushroomed nut, if it can be pushed in great, then do what is suggested by Random Tandem....find a shorter male bolt and a new washer, assemble, then leave well enough alone.
I would hate to see you break the lug.
Good Luck, Ben
I would hate to see you break the lug.
Good Luck, Ben
