The screw of my Seat Post Clamp has worn and I need to get it Off.

[Parkinson021]

Hi If anyone can help me with this problem that would be great.

On my Mountain bike, the Seat Post Clamp or Seat Clamp that adjusts and holds your Seat Post in place has broken. I have a non quick release clamp and the screw that you tighten to adjust the height of the seat post has worn in the inside of it.

Basically My Problem is that I don't know what I should do to get the clamp off the bike as I am happy to buy a new one but I don't know of the method I should use to take off the Seat Clamp.

I tried Drilling the screw with different sized drill bits but it didn't work and a tried a torque wrench but it nearly broke my tool.

I was thinking of buying a Screw or Bolt Extractor but I don't know if that is what I should be using, any advice?

(If a picture is needed I can get one)

[GeorgeET]

Yes a photo would be imperative............

[Bill]

Got some idea of what you are talking about, but if you can please get a couple pictures posted as George said that says a thousand words.

[Painkiller]

(10-28-2012, 10:20 PM)Bill Wrote:  Got some idea of what you are talking about, but if you can please get a couple pictures posted as George said that says a thousand words.

It paints a thousand words, I believe thats the way it goes Bill. I know Robar has some old Bread albums he can check it out for us

[Bill]

ooops Yea I bet he does lol!

[Parkinson021]

There are a couple of photos of my problem.

I've highlighted where I've worn the screw and I want to know how if I can take out the screw with some sort of tool or as recommended to me by a friend use a grinder to take the whole thing off as it is steel, although that could go wrong easily.

[Painkiller]

dremel cutoff wheel and cut the bolt in the center and buy a new clamp as it looks like it is the replaceable type

[xerxes]

I'd cut the bolt in the centre, where the existing slot is using a kacksaw blade - it shouldn't take long.

The bolt is probably a standard size, M6 at a guess, so you could either replace just that, or the whole seatpost clamp.

[GeorgeET]

Yep 10-4 to cutting at the slot with a Hacksaw as we say in USA or Kacksaw as our UK buddies call it, depending where you are located. Than wedge it open remove seat post and replace clamp. If you got a dremel use that. One day I'll get one........

Next time soak with penetrating oil, tap a few times, let it soak for a while tap again a few times and use the right size Allan wrench.

[nfmisso]

Getting a saw blade in the slot is going to be tough - not very much room to go up and down.

Dremel or equivalent will be really fast.

Given that you are getting a new clamp anyway, cut anywhere that you can avoid cutting the seat post or frame.

As George says, get the correct size tool for the job, and this would not have occurred. Also, lubricate the threads.

[Bill]

Hey Auryn,
Can you get just one more picture from above to include that silver metal piece as shown on the second picture on the left side ? Just a hunch but first I would like to see it from the top view before I say anything.

[Bill]

Well I am gonna say this now anyways lol. You have a liplock seat post clamp by salsa (well could be a knock off)! I am still trying to figure out how they work or come off or may cause problems but I seen one of these before. The silver button is actually a stainless steel bolt drilled in the middle so the the allen bolt attaches (screw through it) to it and then tightens up. So yea me thinks it is hacksaw or dremel time.

[nfmisso]

(10-29-2012, 11:40 PM)Bill Wrote:  Well I am gonna say this now anyways lol. You have a liplock seat post clamp by salsa (well could be a knock off)! I am still trying to figure out how they work or come off or may cause problems but I seen one of these before. The silver button is actually a stainless steel bolt drilled in the middle so the the allen bolt attaches (screw through it) to it and then tightens up. So yea me thinks it is hacksaw or dremel time.

Bill - I do not know about the brand, but you are correct about the construction; just like Ikea furniture. The silver button is a cylinder that is cross threaded. This is a much stronger solution than threading aluminum, but you have to be more careful about lubricating the threads because stainless on stainless will gall (cold weld).

[Joe_W]

In general you should grease any thread before assembly. Some even grease the valve nuts to bre really thorough

Question to the PeopleKnowingSuchStuff: I thought that stainless on stainless was less problematic than the combination of two different metals (galvanic element anybody?) like aluminum and steel (for example). Could you give me a hint on why even with similar metlas there is such a big problem? I'm not frightened of physics...

[nfmisso]

Hi Joe;

if the two metals are the same, cold welding can occur if you get all the air out the gap, and everything is clean. This is a big problem in space.

aluminum is problematic with stainless; for some reason aluminum gums up stainless. electro-polished stainless steel hardware is far more resistant to galling with aluminum; thus indicating that surface roughness comes into play.

copper alloys (brass, copper, bronze) with almost any metal will not be a problem.

not much science, just Engineering experience.