My carbon fork came with a starnut in it from the bike shop who originally assembled it, I've heard this is a no no but the shop isn't a jack ass shop and it hasn't given me any problems so I haven't thought about it till now. I had the steerer tube cut just a little bit today and the star nut now is too shallow for the plug type steerer tube cap (which supports the steerer tube from the stem's clamping pressure) to compress the head set, it just bottoms out.

What I need to know is what I should do, it doesn't seem like you can get that star nut out so I'm assuming I need to push it down a bit, what would be the best way to go about that? It only needs to go down 5 mm or so.

Is it a carbon steerer tube? I thought that one would just break immediately upon star nut installation. You can tap a star nut out, just go all the way down the steerer.

Plug type steerer tube cap - do you mean a compression plug like this? If so, that eliminates the need for the star nut - it is the carbon steerer tube alternative star nut. Adjusts the headset.

Of the ~10 forks I've owned, this works on exactly one of them. The 'hole' doesn't go all the way down on most forks these days.

With a star nut installation tool. I would be nervous riding a fork that had a star nut in it.

That's true, on my cross and mountain bikes it does go through, but not on my road bike.

I'll try tapping it down, when I say plug type cap it's basically a normal cap but it's shaped like a mushroom and it has a metal tube that goes inside the steerer tube for about an inch so you can't over clamp the steerer tube and crack it, pretty nice design but it's bottoming out on the star nut. I can actually use that plug as a guide to tap down the star nut. I was under the impression that star nuts were glued in.



The store I bought it from is a pretty major shop with a lot of experience and deals in pretty high end bikes so I'm not too worried about it but I might bring it to their attention next time I'm in.

Carbon steer tube is a no for a star nut. Most carbon forks have an alloy tube. Yes, the star nut can be pushed down.

You did not answer if it is an aluminum steerer tube. If so, you can use the star nut and get a headset cap instead of the compression plug you described (as pictured above?).

No, star nuts are not glued. They basically are hammered in and stay in. You can move it down with a star nut tool.

If it's a star nut in a carbon steerer and THEY put it there, I'd insist that THEY replace it.

Yes it's a full carbon steerer tube and I could definitely take it down to the shop and insist they take it, the club I just joined is sponsored by the shop. They're good guys, who knows why they did it.

That star nut sure as hell should not be in there, that's not safe to ride. Don't ride it to the shop.

I'm gonna guess the new guy (or the old stupid guy) didn't know better, put it in there, then realized it needs a compression plug. Then they just kept it there and didn't tell anyone.

I'm not too worried about riding it to the shop seeing as the bike has 5k on it over the last year...

I'm still taking it to the shop tomorrow and asking the head mechanic at the main store why they put it in there.

Oh, it's not a new fork/new installation? Okay. I thought it was. Either way, that's not acceptable.

Oh no, this bike is from the end of 07' and I bought it from a dealer as a complete in May of 09' new old stock. I'm going to go in tomorrow though and see what they'll do because yah it's probably fine and I've been riding it for a year but better safe than sorry. You guys think it would be totally out of hand to ask for a replacement fork, even though they don't make System Six's they can definitely get the fork. **** I paid $3600 for the bike.

Definitely.. there should not be a star nut in there. That's not safe necessarily; even if it is, that's like buying a car with a muffler half off. It might never fall off, and it isn't noisy, but you know it's there and could fall off. Awful example, but you get my drift.

I dunno if they'll give you a new one, depends if they trust that you didn't put it in there.

A lot of carbon steerer tube forks get aluminium inserts glued inside once the fork is cut to length. It's ok to have a star nut in one of those.

That's what I thought but nope this was hammered down there, not glued. I've always noticed that in one part of the steerer tube it was harder to slide down the spacers and today I noticed that it's where the star nut is so i could be bulging the carbon.

I swear between all the cosmetic defects of this bike I've had so many problems even though it rides so well.

what kind of bike is it? I seem to remember one brand of bikes used a special star nut with their forks. I feel like it was cannondale, but i could be wrong.

My bike is a C-Dale with the over sized fork, I mean that'd be FANTASTIC if it was meant to be like this but if not... I kinda am not cool with having a bike that proved a general rule of thumb wrong.

ah, well check out this and this.

Thank you, I have a feeling this bike store wouldn't blow it but I'm still going to call the shop tomorrow.

I wouldn't worry too much. all the nut/cap do is take up slack and load the bearing. the stem is meant to hold the fork on.

I hope you learned your lesson.

FWIW I'd suspect that getting that *nut out is going to damage the steerer a lot more than leaving it in there/pushing it down a bit.
I'd advise that, a different shaped headset cap, or a whole new fork.

Some carbon forks utilize a star nut design. This is something I have learned the hard way - by encountering it. They are all a little different. You have to check with the fork's OEM to be sure.

Starnut in all carbon steerer tube = Fail