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Proud Thunderchicken ownr
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Discussion Starter · #1 ·
On the weekend, I was about to head out for a ride so I did my usual pre-ride suspension bolt torque checking (some have a tendency to back-off) and I found one rocker (lower) bolt loose.
I took it out, cleaned the threads (all appeared good), put a drop of blue locktite and screwed it back in. Problem time.
The bolt kept turning and never got tight. Balls.

We were in a rush to go out, so I grabbed the old faithful Green Goat back up (which turns out had even more issues but I rode through). On our way out to the trail, I call my LBS and ask if they've got all sorts of helicoils so I could repair it. They claimed to have various sizes so I'm feeling good. Fast forward to 2 days later and I've got time to look at it.

I grab my Allen and give it an unthread ... spin spin spin spin. No lateral movement, just keeps spinning in the frame. Balls.
I get the pliers out to try to pull and turn. No dice.
I get the vice grips and really give it a good turn and pull. No dice.


Before I get too far depressed, are there any suggestions from mechanics? My bike storage is so full at the moment (because backup bike is there) I can't really get into the gritty of it and my LBS is so backed up because of the gorgeous weather it'll be away for 1-1/2 weeks.
- Can I remove the side bolt and give it a gentle nudge through the hole (if it is clean through)?
- Any suggestions to pop that sucker out? I'm figuring the back threads are shot and the front one is there but the shoulder on the bolt won't allow it to catch.
- Since it is not coming out, would some gentle rides damage the frame/rocker?
- Will Pivot comp me a new frame? :D


On the plus side, my wife's Firebird is running better than ever! But I'm stuck struggling my DH bike around unless I fix up the Green Goat.
 

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> /dev/null 2&>1
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Which bolt, can you show it in a pic?

If it's the one I'm thinking of, the lowest one in the rocker arm, which has sort of a conical shape, can you get something thin and flat under it, like a thin paint scraper or putty knife, to supply upward pressure while you rotate ccw?
 

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Proud Thunderchicken ownr
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241 Posts
Discussion Starter · #3 ·
Which bolt, can you show it in a pic?
Ignore the RC4 mounted to the carbon rocker, this is an old photo and I was just seeing if it would fit.

P1030002.jpg

If it's the one I'm thinking of, the lowest one in the rocker arm, which has sort of a conical shape, can you get something thin and flat under it, like a thin paint scraper or putty knife, to supply upward pressure while you rotate ccw?
You are correct as to which bolt it is. I was hunting for a thin pry lever but couldn't find one in my shop (a 6'x8' storage unit in my condo) but just now I remember where one is ...



I just hope that once it is removed, there is enough meat left on the frame to tap in a helicoil. I'd hate to have to get creative and drill it all the way through and use a thru-bolt.
 

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Pivotal figure
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6,361 Posts
If you remove the opposite side's bolt you'll be able to push on that one thru the inside (may have to clean out any excess loctite in there first). Or you can try wedging something thin under the head, maybe a putty knife or similar. There's usually enough material for a helical IF the threaded portion hasn't been deformed. I've seen then get ovalized from riding with the bolt loose and that can complicate things....
 

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Proud Thunderchicken ownr
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241 Posts
Discussion Starter · #5 ·
Thanks Ken!

I'd considered my situation complicated .. as usual.
Extracted the bolt using a punch and impact ratchet.

I ordered in a M8x1.25 x 80mm (and a 120mm just in case) helicoil and am going to take it over to friend who is a machinist to drill for me. I'm pretty sure this has to be balls on straight so I don't want to take chances with me just eyeballing it.

I really hope it doesn't get to Plan C; grind down frame and weld a nut to it.
 

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650b me
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There is life after stripping

Here's a photo of my helicoil-ed Mach 4. I was using a quality torque wrench at the time, but still managed to strip the threads in the frame. This was over the winter during the non-riding season. So far, it's holding up just fine. :thumbsup:

View attachment 889469

Good luck!
 

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Pivotal figure
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The straighter the better! I have a jig to mount the frame on the mill so it's dead straight and centered, you just use the other side's threads to attach the frame (which is most likely what your machinist friend will end up doing). PlanC should never even come into play! At the very worst you could drill out the threads and use a thru bolt before resorting to welding....
Thanks Ken!

I'd considered my situation complicated .. as usual.
Extracted the bolt using a punch and impact ratchet.

I ordered in a M8x1.25 x 80mm (and a 120mm just in case) helicoil and am going to take it over to friend who is a machinist to drill for me. I'm pretty sure this has to be balls on straight so I don't want to take chances with me just eyeballing it.

I really hope it doesn't get to Plan C; grind down frame and weld a nut to it.
 

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Proud Thunderchicken ownr
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241 Posts
Discussion Starter · #8 ·
Step 1,2 Complete

Secured frame in lathe.
Leveled all sides and verified with guide pin.
Drilled clean through.
Tapped holes (using lathe) from each side as the tap was just a hair too short to run clean through.
Cranked in some 14mm heli-coils.

Feeling pretty ok now, less sick to my stomach.








Many thanks to my buddy Gary and his dad and his dad's random collections of spare parts. :thumbsup:
 

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Proud Thunderchicken ownr
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241 Posts
Discussion Starter · #9 ·
Update

Bolted rear triangle on with no shock. Everything cycles so smooth.
Committed to re-build and re-assembled everything.
Cycled with shock installed and no air, smoooooooooothhhh.

I will have to do a few rides once the rains go away before I can give it the final ok.

Video
 

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> /dev/null 2&>1
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Nice fix! I hope I never have to deal with that. With the exception of a threaded bb, any threaded hole in a frame has a date with death. I wish designers would find ways to make it a thru bolt every time, although I know that's not always possible.
 

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Proud Thunderchicken ownr
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241 Posts
Discussion Starter · #11 ·
I may be through-bolting it yet. I've got a mystery creak somewhere and I'm betting it is link.
Any way I look at it, it is going to be an expensive year. :(
 

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Mine did the same thing. LBS helicoiled it, has held for a year until i tried to remove the bolt for a strip down and the helicoil came out. easy to fix though.

Just keep an eye on it and you should be fine.
ive ridden the **** out of mine and its held.

I also stripped the dérailleur hanger thread lasted month. i fixed it with a chain ring bolt by drilling the hole out to 10mm. Personally i think this is a far better system than a threaded frame.
 

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I've noticed recently that the same lower rocker bolt on my FB has been coming loose after each ride or two. Cleaned,used loctite and properly torqued but didn't hold. I'm probably going to bring to LBS but is this cause for concern?
Thanks
 

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Proud Thunderchicken ownr
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241 Posts
Discussion Starter · #14 ·
Next time it is loose, inspect the threads inside and see if they are still looking ok.
Thread the bolt half way in, sans rocker, and see if it will wiggle. If it's sloppier in there than a 70 yr old prostitute, you got an issue.

Chances that the bolt is giving out before the frame threads is pretty slim.
 

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Hey - long time lurker, first time caller... can I ask how the helicoil is holding up for people that have tried this fix? I just had both bolts on the same pivot point rip out of the frame, trying to decide what to do. Oddly gave me no problems before, never had loose bolts, just pop. And this happened right after LBS did a full bearing replacement, not sure how that plays into the situation.

Any advice appreciated - thx!
 

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Proud Thunderchicken ownr
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241 Posts
Discussion Starter · #16 ·
Mine worked until I cracked the frame a month later. I've JUST (last night) finished building it back after get some welding/re-enforcing done so I will let you know if it survives tonight.
If it fails, I will drill it bigger and machine a long stainless rod that goes clean through both and nut both ends.

It is my backup bird now as I have ... n+1=n where n=firebirds
 

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Proud Thunderchicken ownr
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241 Posts
Discussion Starter · #17 ·
The old bike felt amazing, everything was going smoothly ... then the derailleur pointed backwards.

All the heli-coils worked fine though for the first 10k getting to the trails and the 2k on trail.
:(
 

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650b me
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1,486 Posts
Hey - long time lurker, first time caller... can I ask how the helicoil is holding up for people that have tried this fix? I just had both bolts on the same pivot point rip out of the frame, trying to decide what to do. Oddly gave me no problems before, never had loose bolts, just pop. And this happened right after LBS did a full bearing replacement, not sure how that plays into the situation.

Any advice appreciated - thx!
Mine is holding up fine, almost a year since installing the heli-coil.

Sorry to hear about your frame. Not trying to place blame, but it sure sounds suspicious that this happened right after your LBS did a full bearing replacement. Have you talked to them about it? I hope you're able to repair it.
 

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650b me
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The old bike felt amazing, everything was going smoothly ... then the derailleur pointed backwards.

All the heli-coils worked fine though for the first 10k getting to the trails and the 2k on trail.
:(
Derailleur pointed backwards? What does that mean?
 

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Proud Thunderchicken ownr
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241 Posts
Discussion Starter · #20 ·
Cranks jammed, I looked back and my derailleur was on the backside of the cassette not below the axle like it should be. I cried a little. Luckily it was a sale priced Zee from CRC so I was only out $45.
 
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