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Discussion Starter · #1 ·
Might I ask the board's wisdom?

I managed to shear off one of the studs at the bottom of my CB350K4 fork. This is the 8x50 stud that runs through the bottom holder keeping the front axle in the forks.

I've been able to source a replacement fairly cheaply. Any tips getting the old one out, and the new one in?

Many thanks,

K
 

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Discussion Starter · #2 ·
So there didn't turn out to be too much of a trick to this, but I'd like to report what I learned, in case someone else comes looking.

You need a vice. Clamp around the flat part of the fork, right down at the bottom, by the stud.

Penetrating oil helps a lot. So does cleaning off the flat portion of the existing stud, which is a great place to grab vice grips.

There was a very noticeable cracking sound when the stud came loose. And it was work turning it out, all the way.

Clean the threads up well before running the new stud in. You can run a nut down the opposite, threaded side of the stud to make it easy to turn in with a wrench. Back the nut off a bit, every few turns, to make sure it still comes loose.
 

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I have a similar problem. I may have stripped the threads on the nuts/studs on the bottom of the forks. Using an incorrect description in the manual, I torqued all four nuts to between 30 and 35 ft lbs. I'm probably not the first person to do this, but it doesn't lessen the "don't I feel stupid" factor. After I realized the error, I was able to thread three of the nuts on and off no problem, and they can be tightened. But one nut and stud is definitely boogered. I don't know how long the studs are supposed to be, but they could be stretched as well.

I'm thinking I might be able to chase the stud threads and just find a replacement nut. If not, where can I source the studs? BTW, my studs do not have a flat on the unthreaded portion. Do you think vice grips are enough, or should I let a real mechanic handle this?
 

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Vise grips will work fine. A little heat on the fork leg is a good idea, warming the aluminum will help it let go of the stud..
 

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I've used a pipe wrench on really stuck ones where a vise grip didn't have enough leverage. Check you Honda dealer, part number 92700-08050
 

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Discussion Starter · #6 ·
barab63: I'm pretty sure the manual torque got me, too. I've almost always done those kinds of fasteners by hand, but for some reason, I got inspired...and stripped the fastener out.

Sorry if I wasn't clear. Both the original studs and the replacements I sourced had a section of unthreaded round, in the middle. That section wasn't "flat" as in square or hexagonal. It's round, just unthreaded, like a pin or dowel.

The replacement studs I found had part number 92900-08028-3B. I believe I found mine on eBay for a couple bucks a pop.

I don't know who these real mechanics are you mention, but I imagine they use vice grips, heat, and elbow grease like us fake mechanics. If you absolutely cannot grab and turn it out with heat, penetrating oil, and grippers, you may end up having to cut it flush at the hole and drill it out. At that point you might very well consider taking it to a full-timer, either a mechanic or a machinist. I haven't heard of anybody who gets fasteners out of aluminum clean 100% of the time, but folks with a lot of practice get lucky a lot more often.

Under no circumstances purchase EZ Outs, alias spiral screw extractors, or trust anyone who says you should.
 

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Thanks for the info. While thinking about the stud issue, I've worked up to removing the dampener rod retaining bolt found in the bottom of the fork. I got one out without heat, but the second one won't unthread from the dampener rod. Any suggestions how to remove the bolt? Im thinking of using a heat gun and penetrating fluid. I got the top cap off so is there a way to go in from the top?
 

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Before you do too much damage to the case, you might want to look into electro discharge machining or EDM. This will remove the broken stud without damaging the fork case. It is used in aircraft maintenance where parts are too costly to just toss.
 
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