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Old 06-22-10, 09:14 PM   #1
ClarkinHawaii 
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Supporting the fork while hammering the star nut?

I had one hell of a time installing a star nut in a cheapo aluminum fork a few months ago. Went in crooked and I couldn't straighten it out--fortunately it was straight enough that the bolt screwed in ok and it ended up doing its job in the end, but it was a nightmare. End of steer tube kinda mangled.

Now I need to install one in a very expensive carbon fork--everybody tells you how to hammer on the thing with a socket or whatever, but nobody says how you're supposed to hold the fork while you're doing this. I don't have a vise or a tame gorilla to hold the carbon fork steady whilst I do the deed.

The "head lock" sounds good to me. I don't care about the weight of that extra long bolt. Problem is that the fork steerer will be used uncut, and they don't supply the interior bolts in head locks long enough. Is the interior bolt of a common enough threading that I could find a foot-long one at home depot? I plan on slapping on a locking spacer and removing the interior bolt anyway, not leaving it permanently attached.

If there is not some way that I can do the star nut myself, unassisted, I'll have to jury-rig a head lock.

What do you suggest? Thanks

Edit: Inspiration has struck--Why not use a very long bolt run from the head cap down through the crown and out the hole at the bottom of the fork's cleft, where it will be screwed into one of those expansion bolts like you use behind drywall. Do the preload, put on the locking spacer and remove the "head lock". Sound feasible?
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Old 06-22-10, 09:56 PM   #2
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Originally Posted by ClarkinHawaii View Post
I had one hell of a time installing a star nut in a cheapo aluminum fork a few months ago. Went in crooked and I couldn't straighten it out--fortunately it was straight enough that the bolt screwed in ok and it ended up doing its job in the end, but it was a nightmare. End of steer tube kinda mangled.

Now I need to install one in a very expensive carbon fork--everybody tells you how to hammer on the thing with a socket or whatever, but nobody says how you're supposed to hold the fork while you're doing this. I don't have a vise or a tame gorilla to hold the carbon fork steady whilst I do the deed.

The "head lock" sounds good to me. I don't care about the weight of that extra long bolt. Problem is that the fork steerer will be used uncut, and they don't supply the interior bolts in head locks long enough. Is the interior bolt of a common enough threading that I could find a foot-long one at home depot? I plan on slapping on a locking spacer and removing the interior bolt anyway, not leaving it permanently attached.

If there is not some way that I can do the star nut myself, unassisted, I'll have to jury-rig a head lock.

What do you suggest? Thanks

Edit: Inspiration has struck--Why not use a very long bolt run from the head cap down through the crown and out the hole at the bottom of the fork's cleft, where it will be screwed into one of those expansion bolts like you use behind drywall. Do the preload, put on the locking spacer and remove the "head lock". Sound feasible?
It is not advised to use a star nut in a carbon fiber fork. They make a wedge for that. I don't understand the concern about a long reach bolt. The wedge can be at the top, regardless of leaving the steerer full length.
example: http://cgi.ebay.com/VP-COMPRESSOR-TO...-/290446267467

You use spacers with the stem such that the stem and spacers extended slightly above the top of the steerer. This gives you the needed bearing preload through the cap. Don't makes this any more complicated than it needs to be!

Don in Austin
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Old 06-22-10, 10:03 PM   #3
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Carbon fork with aluminum steerer--sorry.
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Old 06-22-10, 10:06 PM   #4
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Just how much steerer are we talking about that is uncut, above the headtube anyways? There is a max allowable steerer height typically 40-50mm worth of spacers + stem. The starnuts take a standard M6 bolt, usually with a low profile head and a regular head is just as acceptable.

As for holding the fork you can put the fun between your legs and hammer it in, while holding the fork with your hand as well.
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Old 06-22-10, 10:11 PM   #5
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Just support the fork on a block of wood with maybe a towel wrapped out it at the crotch. You don't have to push the star nut in very far at all. Rapid taps with a medium hammer will work better than slow taps with a heavy hammer. If you are worried about the start nut going crooked screw a bolt into it to hold it straight and hit the end of the bolt.

Don't be too scared. Carbon fiber is strong.

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Old 06-22-10, 10:35 PM   #6
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Just how much steerer are we talking about that is uncut, above the headtube anyways? There is a max allowable steerer height typically 40-50mm worth of spacers + stem.

The starnuts take a standard M6 bolt, usually with a low profile head and a regular head is just as acceptable.

As for holding the fork you can put the fun between your legs and hammer it in, while holding the fork with your hand as well.

Totally uncut Winwood muddy--Actually about 140 mm worth of spacers + stem--and stem is 120mm@125 degrees--only ridden by old man to church on Sundays--no speeds in excess of 45mph. Insists on drop bars because they remind him of when he was young stud. Sucks but what are ya gonna do?

This is what I did last time--sounds easier than it is.
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Old 06-22-10, 10:56 PM   #7
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Just support the fork on a block of wood with maybe a towel wrapped out it at the crotch. You don't have to push the star nut in very far at all. Rapid taps with a medium hammer will work better than slow taps with a heavy hammer. If you are worried about the start nut going crooked screw a bolt into it to hold it straight and hit the end of the bolt.

Don't be too scared. Carbon fiber is strong.

Don in Austin
Do that around here and you're fired. There is NO reason to subject a CF fork to that kind of abuse before it is even installed.
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Old 06-23-10, 12:02 AM   #8
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How about using one of those compression plugs (designed for carbon steerers) in an aluminum steerer? Would it provide a good enough grip to preload properly, or would it slip against the aluminum?

Again, I'm just talking about initial set-up--not expecting it to hold tight forever like a star nut.
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Old 06-23-10, 12:33 AM   #9
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How about using one of those compression plugs (designed for carbon steerers) in an aluminum steerer? Would it provide a good enough grip to preload properly, or would it slip against the aluminum?

Again, I'm just talking about initial set-up--not expecting it to hold tight forever like a star nut.
You can use a compression plug sure. I have to say the plan you have for your fork install is quite odd.
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Old 06-23-10, 10:02 AM   #10
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Odd fork for odd person.
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Old 06-23-10, 10:10 AM   #11
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Old 06-30-10, 05:24 PM   #12
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Do that around here and you're fired. There is NO reason to subject a CF fork to that kind of abuse before it is even installed.
Thank God I don't work where you do then. I was advocating tapping the star nut in with about an 8 oz hammer. If that hurts the fork then its not fit to ride across town on.

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Old 06-30-10, 05:30 PM   #13
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You don't hammer on a nut, you use pliers or a pipe wrench.
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Old 06-30-10, 06:28 PM   #14
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If you have to hit a star nut so hard you can't hold the fork by the steerer with your hand, something's not right.

I too would fire a mechanic I saw either hammering on a carbon fork with the dropouts on the floor, or by supporting it at the "crotch" and hammering.
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Old 07-01-10, 03:38 AM   #15
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You don't hammer on a nut, you use pliers or a pipe wrench.
For installing a star nut into a steerer???

Please describe your technique.
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Old 07-01-10, 10:36 AM   #16
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Saw 8" off a broom handle. You want the end with the dome - not the end with the bristles. Mark intended depth of star nut on broom handle. Tap star nut gently in.

Domed end is perfect fit for nut, and broom handles seem to perfectly fit 1" 1/8th tubes.
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Old 07-01-10, 11:25 AM   #17
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There is a star nut tool that will center and position a star nut at the proper depth.
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Old 07-01-10, 12:23 PM   #18
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Thanks for the help, Guys. Considering the cost of the new fork I'm going to be working with and the apparent disability I have which renders me incapable of seating the star nut as easily as you can apparently do it, I included this in my latest order. For $11.53 my problem is solved.

http://www.chainreactioncycles.com/M...px?ModelID=293
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