How to remove a stuck pivot bolt

ClintBX

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Mar 6, 2014
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419
Hi ESFMs,

I'm in the process of restoring an old frame. And finally getting around to disassembling it.

All was going smooth until I got to removing the rear suspension coil. I managed to remove one pivot pin/bolt (what do you call that piece?) But then that second one.... Well, is enough for me to start a thread on endless sphere for help.

I was able to remove the bolt itself but the pin side that anchors the coil to the frame just refuses to back out. It spins freely, do I know it isn't rusted or fused in any way.

I've tried threading the bolt in by a few threads and hammering it with a mallet,
I've tried lubing it AND degreasing it, then hammering it again,
I've tried letting it sit in lube/degreaser over night, then more hammering,
And just last night out of sheer desperation, I Dremeled off the head of the bolt (on the pin side) to hopefully get it to back out the other way. Hammered it using a centre punch.
I also tried to use the heat and ice method but I don't quite know how to do it correctly. I was using a hot air gun to hear the surrounding metal and an ice pack on the bolt/pin head side.

Oh, I also tried drilling into it but I think my drill bits are too weak to cut into it. It's a steel bolt.

I've exhausted everything I can think of. Have any of you had this issue before? What haven't I tried yet?

Clinton
 
Maybe you can show a photo from a few angles and write what bike it is.
 
Here some quick snaps I took of it. I forget to turn on the flash, so excuse the poor lighting. I'll post done fresh ones tonight.
 

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I would try using a big C-clamp and press it out. You need something on one end to push on (bolt head) and something with a recess (like a wrench socket) on the other side so has room to move out.

There may be a groove in the pin from wear that is acting like a lip, preventing it from moving easily.

Hammering didn't work because it's too flexible and just bounces.
 
For those having trouble seeing the image clearly, I have enhanced it a bit as shown below.

And yes, you will need to use hydraulic pressure (such as from a clamp or gear puller) to push that puppy out.
Been there, done that.



P.S. if you can find a spare hollow "pin" then you could conceivably use a bolt to pull that puppy out. Something like the following:

|| <socket> ------ =====|

where:

|| is the head of the bolt
<socket> is some hex socket that has a bigger diameter than the stuck "pin"
------ is the bolt passing through the stuck "pin"
===== is the spacer "pin" used to press out the stuck pin
| is the nut
 
Air hammer?
They are cheap at Harbor Freight, but you need a compressor.
 
ClintBX said:
I was able to remove the bolt itself but the pin side that anchors the coil to the frame just refuses to back out. It spins freely, do I know it isn't rusted or fused in any way.

When you say it spins freely, do you mean spins relative to the frame, relative to the shock, or both? (I assume since you were able to remove the other bolt and pin, that there's not compression/tension being applied by the shock to the stuck pin.)
 
E-HP said:
ClintBX said:
I was able to remove the bolt itself but the pin side that anchors the coil to the frame just refuses to back out. It spins freely, do I know it isn't rusted or fused in any way.

When you say it spins freely, do you mean spins relative to the frame, relative to the shock, or both? (I assume since you were able to remove the other bolt and pin, that there's not compression/tension being applied by the shock to the stuck pin.)

Spins free relative to both the frame and the shock. I think it's as fechter suggested, there might be a groove or a lip keeping locked in place.

Just bought a c clamp today. I'll see how it goes tonight.
 
Like promised, here some clearer pics.
 

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ClintBX said:
Like promised, here some clearer pics.

I think this was asked before, but what bike/frame is this mounted on? Just judging by the pic, the "shock" is on the lower end, with no adjustments except pre-load. May or may not have oil damping. It could be that it wasn't meant to be serviceable or replaceable.
 
Okay, I tried the C clamp approach but I was having difficulty keeping it in place, and when I did I couldn't really exert enough force to budge it.

Maybe I got the wrong type of C clamp? It's the type with pincer design.
 
E-HP said:
ClintBX said:
Like promised, here some clearer pics.

I think this was asked before, but what bike/frame is this mounted on? Just judging by the pic, the "shock" is on the lower end, with no adjustments except pre-load. May or may not have oil damping. It could be that it wasn't meant to be serviceable or replaceable.

This is a frame I restored previously. I've serviced this frame before and the first time, I had a much easier time getting that pivot pin out.

I suspect that I might have over tightened that bolt when I was starting to notice a bit of side to side play in the linkage.

I don't know the make of this frame. It was unmarked when I found it.
 
ClintBX said:
Okay, I tried the C clamp approach but I was having difficulty keeping it in place, and when I did I couldn't really exert enough force to budge it.

Maybe I got the wrong type of C clamp? It's the type with pincer design.

Bummer.

The style I had in mind was like this:
C clamp.JPG

Another possible approach is to find a heavy chunk of metal with a hole in it you place on one side, then beat with a hammer on the other side. The weight gives you some inertia to generate force with so the hammer doesn't just bounce off. You'd need to thread a sacrificial bolt in the side getting pushed.
 
I would drill it off, to avoid damaging the frame with pressure or hammering. Then re-assemble in a more standard way: Stainless pivot bolt, alu bushings, PTFE washers, Nylock nut.
 
Funny, I never have this kind of problem with my one-piece bicycle frames.
 
MadRhino said:
I would drill it off, to avoid damaging the frame with pressure or hammering. Then re-assemble in a more standard way: Stainless pivot bolt, alu bushings, PTFE washers, Nylock nut.

I might have to do that. I tried already some drill bits but they just wouldn't cut into it. I'm not sure what my drill bits are made of but they're not fit to penetrate this type of steel. Any recommendations?
 
Titanium tip bits should be able to cut into it, just don't let it overheat.

If you do want to try pressing it out, gently heating the frame while avoiding heating the pin could go a long way. But I think MadRhino is right, drill it out and use a bolt assembly.
 
dustNbone said:
Titanium tip bits should be able to cut into it, just don't let it overheat.

If you do want to try pressing it out, gently heating the frame while avoiding heating the pin could go a long way. But I think MadRhino is right, drill it out and use a bolt assembly.

How do you mean by bolt assembly?

Also, once I've drill through it, what then? Will drilling it automatically make the pin loose or is there something else I have to do to get the pin to release me....uh, I mean the frame?
 
If the pin is spinning free, then it might just spin when you try to drill it. Since it is free it doesn't need any heat either. It just needs a lot of force to push past whatever is holding it. If you can get it to drill, you might only need to drill out the first few mm on the end to get rid of the ridge holding it.
 
You won’t have to drill much to free both sides off the frame. To free it off the shock eyelet, you can hammer, press, heat, whatever.

Any professional cobalt alloy drill bit will do. Yours are probably worth the cost of one 1/4’’ bit for the whole kit of sh*t. I don’t like Ti bits but they are an acceptable cheap solution for this task. Check on Amazon or Home Depot for a kit, or buy one piece at auto parts. Drill America M35, Irwin, Dewalt... any reputable brand cobalt drill bits. Cobalt bits can be sharpened, good investment.
 
Making progress! I got around to getting the correct type of C clamp. Using a large nut and some tape to cover the side of the pin I'd previously decapitated and a bolt partially threaded on the other end, I managed to get it through most of the way. I had to find a bolt with a flatter profile so that the C clamp wouldn't slip off so much.

Now it seems to be stuck on the other end of the pin. I was hoping that getting it sliding would be enough for me to pull it through with my finger or some pliers, but no such luck. Now, it's hanging out the side.

I tried to press it through with the C clamp some more but the clamp tends too slip off the head of the bolt before enough pressure can be applied.

I Dremeled about half of the pin off in hopes that I can just press it back in enough so I can just pull out the suspension coil. But again, the C clamp just slides off the pin before adequate pressure can be applied.

And lastly, I Dremeled notches into the pin in hopes that I can maybe pincer it into submission. But I later realized that the notches would have to be deeper, below the level of the eyelet that's holding it for that to work.

Seems this is fighting me to the bitter end. Anyway here are some shots of the "surgery"
 

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Dang, stubborn little bugger.

Possibly it was seized in the shock eye and the whole eye insert was spinning in the shock. Some penetrating oil won't hurt. If the shock is toast, some heat may help too, but you want to avoid heating the frame piece enough to change the temper.

If you just can't get it to budge out any more, it might work to cross drill the shock eye (if that's possible) and stick a pin in the hole to keep the thing from spinning. Then you could drill out the remains. Anything that keeps it from spinning may allow drilling it out.

Alternately, since you got it to move, if you put the big nut on the back side and place it against the floor or solid object, you might be able to hammer the rest out.
 
fechter said:
Dang, stubborn little bugger.

Possibly it was seized in the shock eye and the whole eye insert was spinning in the shock. Some penetrating oil won't hurt. If the shock is toast, some heat may help too, but you want to avoid heating the frame piece enough to change the temper.

If you just can't get it to budge out any more, it might work to cross drill the shock eye (if that's possible) and stick a pin in the hole to keep the thing from spinning. Then you could drill out the remains. Anything that keeps it from spinning may allow drilling it out.

Alternately, since you got it to move, if you put the big nut on the back side and place it against the floor or solid object, you might be able to hammer the rest out.

If by shock eye, you mean the little barrel that sits within it, then that's my suspicion too. I think that a lip may have formed on that one end of this barrel, which would explain why it's been holding on so damn tight on both ends of the pivot.

I tried giving it a finishing whack but I think it's still beyond sick means right now.
 
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