I’ve just bought a bike for the frameset for a 1x commuter beater project. It’s a Pinnacle Arkose from ~2015. Alloy frame, fully carbon fork and steerer. I took the fork off to replace the gritty headset bearings and notice that they've used a metal star nut and that it's not centred properly.
This is the fork the bike originally came with. Should I be worried/try to remove it and replace with a proper carbon compression plug I have? I've seen people gently drill out the top rivet on the nut to then remove, but the headset can be tightened fully so maybe just leave it?
Cheers
by HarryTheCaveman
16 Comments
were i work at, we just yank them out, but i can see why you dont wanna do that on a carbon steerer.
i have honestly no good idea to get it out without damage if it really sits in there, but im pretty sure metal star nuts are not supposed to sit in carbontubes, so i would hesitate to trust it as is.
Someone correct me if I’m wrong, but there shouldn’t be a star nut inside a carbon steerer in the first place.
I’d say, if you can get it out without damaging the steerer, do it and replace it with a proper expander.
This should not be in a carbon steerer to begin with. I would drill out the threads carefully and then replace with an expander plug. Make sure to triple-chrck if the star nut has damaged the carbon.
Is the steer hollow through? Then oerhaps whack it out the other end
Should have never been in there unfortunately, in a metal steerer I’d just slam it down and forget about it but you don’t want to do this on a carbon tube. Drilling will be hard to because you can’t clamp the fork properly. If you can live with a slightly lower setup the cleanest option is to shorten it so the star nut is cut out. My fear is that an attempt to pry it out another way will likely damage the fork.
Take a rotary tool to it. Use a small metal grinding bit (don’t know what it’s called) and remove material from where the star meets the threads. Then grind trough the star itself. Best would be to spilt it in two (three if necessary) between the “fingers” so you don’t touch the carbon. Removing the lower star is harder. You would need to cut (by grinding in a circular manner) the threaded shaft first.
Edit: I wouldn’t risk drilling it out. If your drill bit gets stuck to the star nut it might damage the carbon.
Could you get a Dremel in there and carefully cut the flanges?
You need to cut it out carefully, probably best with a dremel, then clean the carbon and apply an even coating of epoxy resin to shore up the scraped areas, and I think you will be ok to continue using it.
I would expect a drill to twist the star nut and make the damage worse. Without a proper star nut the steerer could already be split due to not being able to support the stem clamping force. Something more precise to extract it in pieces is probably the best idea, or replace.
Depending on length of the the steeerer I’d be tempted to cut below the star nut and run it slammed- obviously depends on a few other factors!
Can you afford to lose any of the steerer? Because the easiest option is to cut the steerer below the star but, which looks like it would reduce the length by about 20mm.
Thin metal blade. Will take time but saw off one of the legs of the nut. The rest will come off.
I would drill out the threaded part and use dremel to grind the metal plate with stone bit. At some point ”the wings” become detached.
Finish with epoxy to the scratches inside the tube.
Whatever you do: when you finally have the star nut out, go and shove it up the back end of the moron that put the star nut into a carbon tube.
90° angled pointed nose pliers, bend each flap upwards until you can pull it out.
UPDATE: Got it out 👍🏼
It’s a cycling shop’s own brand bike from 2015, so very much built to a budget which is why I suspect a star nut has been used instead of a compression plug. As people have suggested, I’ll clean and apply a bit of epoxy to the inside. The plug I have is quite long so think we should be good.
Cheers gang ✌🏼
https://preview.redd.it/j605rqcr4wzg1.jpeg?width=3024&format=pjpg&auto=webp&s=0728c3297cc48ce4fc1902050c87b0cd3529488f