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HELP! Frozen Rotor Bolts On My King Hub!

748 Views 14 Replies 9 Participants Last post by  myitch
When using the 3mm allen key to remove the rotor bolts, they stripped out. All friggin 6 of 'em. I even tried using a screw extractor with all my weight on them with a power drill. The screw extractor just continues to make the hole deeper and I'm running out of metal on the bolts.I tried using a hacksaw to make a cut for a screw driver. Stripped out and still stuck. I just squirted them with WD-40 and hope they loosen up enough overnight.

I might try filing the bolts square so I can fit a wrench on. That might be the last resort since if that strips out, I won't have anymore of the head left to remove the bolt. Plus that will take gobs of time.

I'm afraid to try a bike shop as they might just hack it and ruin my King hub. I made the mistake of using blue loctite to keep the bolts from coming loose, which hasn't been a problem before when removing. I won't do that again.

Any other ideas out there? HELP!
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I am guessing you are talking about the three 3mm allens per hub which hold the Discotech adapters onto the hub? I can't figure out what else would take a 3mm allen head bolt. Rotor bolts are always t25 torx head bolts, NOT allen. Can you clarify what bolts you are talking about and maybe we can assist you?
Its an ISO hub, Hope rotor. It has six 3mm allen fitting, mushroom heads. I don't know about Hopes new stuff. If it were at least a button head, I might have more material to grab onto. No such luck there.

So, theres the std 6 bolts. All of them are frozen!! At this point, what type of head they were doesn't matter, the inner material is gone so whether torx, allen, or whatever, theres not much material left in there, even for the screw extractor to grab.

I might have to carefully drill all the way through or something, but that is extremely tricky since I can't ruin the soft aluminum threads of my precious King hub.
Maybe I'll end up drilling through and putting in a helicoil, last, last resort of course.

Heating, tapping, 24 hours to a week of penetrating oil, but I don't know if that'll work with Loctite in there.

More info. Frozen or Broken Taps and Fasteners.pdf
Had this happen to me on the same kind of button head hex bolts.

In the past, two things have worked:
1) Cut a line in the bolts with a dremel and use a flat head screwdriver to extract the bolts. Sounds like you did the same thing but with a hacksaw and it still failed.
2) Use a screw extractor to drill off the heads of the bolts, remove the rotor, and then the bolts come out easy with pliers, a screw extractor, or a screwdriver (if I cut a line in them with a dremel first).

It seems that the thing that actually is binding the bolts (keeping them from unscrewing) is the friction between the bolt heads and the rotors, not the friction of the threads in the hubs. At least, that has been the case for me in the past.


Oh, and when you finally get the bolts out go and get some torx head bolts. Those button head hex bolts suck.
I use blue Loctite on all of my rotor bolts. No problems.

Try cutting a slot in the heads and use a screw driver to remove. If that fails drill off the bolt heads. When you remove the rotor the bolts should be protruding enough to grab with vice grip pliers and twist out.

Be sure to use Torx head bolts (and blue Loctite) next time.
depending on what the material the bolts are they may have cold welded them selves to the hub. you may be f*cked. I always use grease and lock-tite
it was blue loctite. any other color would be too permanent or strong a bond.

i did try the screw driver with both a flat blade AND a screw extractor. its been sitting with WD-40 on it since last night. hopefully it penetrated the bond somewhat.

i'm going to pick up a hand impact driver. that might break the bolt loose. only thing is those come with only screw driver fittings. and theres no more fitting left on these bolts.

if that doesn't work, i'll have to drill through, then try a screw extractor that goes inside the remaining bolt material. (see my PDF file link above)

next: PRAY! my precious King!
This works:
Drill off the bolt heads. When you remove the rotor the bolts should be protruding enough to grab with vice grip pliers and twist out.
myitch said:
i did try the screw driver with both a flat blade AND a screw extractor. its been sitting with WD-40 on it since last night. hopefully it penetrated the bond somewhat.
Note that WD-40 is not what you should be using, it is designed to prevent rust. Use a good penetrating oil that is designed to migrate into the threads. The best I have ever found is called Worth Rost Off, a German Made penetrating oil.
All of my rotors have come with Allen head bolts so far. The Hope rotors I have (two piece '05 Mono Mini) came with a Torx wrench and Allen bolts! The other ones I have a Aztec and Shimano, both also came with Allen head bolts.
Never use allen head bolts on rotors... NEVER. If a company is dumb enough to include allens in the brake kit... get torx ones to put in. Steel for sure. As many have said, blue loctite, but just enough to coat the threads, no excess is needed.

myitch - please post a pic before you tear it up anymore. I would like to see this very much.
Sounds like the bolts were overtorqued to begin with.

Also, not all allen wrenches are created equal. I stripped a couple on my old Minis with a hardware store bought set... swotched to some Park Pros, got them all out.

I finally got the bolts out. The Craftsman Hand Impact Driver did the trick. Heres what I did:

1) Dripped WD-40 with the hub rotor side down, to trap the solvent in the hole of the screw.
2) Used a dremel tool (much better than a hacksaw, why didn't I think of that? Thanks BCBlur!) to make a slot for a flat blade screw driver.
3) Used the largest flat blade on the Hand Impact Driver.
3) Apply pressure on the Driver while turning counterclockwise as you pound the Driver.
4) Smiled as it came loose to keep up my motivation!

I kept having to hit it multiple times to first break the bond, then to continue driving the bolts out. This is an amazing tool. Having it sit overnight with the WD-40 probably also helped. Thanks for all the advice and support during my time of need (it was a stressful time as I'm sure you all can relate).

Well, a few lessons learned. I DID make the mistake of using red loctite, not blue as I had thought. I'm not sure why I did that one! Probably ran out of blue and in my laziness settled on red. Never again.

I'm switching to torx or button head allens, not mushroom heads. Maybe even get hardened allen bolts. The ones that came with the brakes were too soft. Button head allens would be good since they have a deeper hole, more material for the allen wrench to grab onto. I really don't think Torx would have been any better really, unless they had a deep head on them. And with a button head the profile is taller, so in a pinch you could file it square and use a wrench or the same method as above.
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Oh, yeah, no pics. I thought of that actually, but in my zeal, I just wanted the damn things off!

Thanks again, boys!
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